Sandoz Methylphenidate Product Monograph

ACTION AND CLINICAL PHARMACOLOGY

Methylphenidate hydrochloride is a racemate consisting of a 1:1 mixture of d-methylphenidate (d-MPH) and l-methylphenidate (l-MPH).

Methylphenidate hydrochloride is a mild central nervous system stimulant with more prominent effects on mental than motor activities.

The mode of action in man is not completely understood, but its stimulant effects are thought to be due to cortical stimulation and possibly to stimulation of the reticular activating system.

There is neither specific evidence, which clearly establishes the mechanism whereby methylphenidate produces its mental and behavioural effects in children, nor conclusive evidence regarding how these effects relate to the condition of the central nervous system (CNS).

Pharmacokinetics

Absorption

Methylphenidate hydrochloride is rapidly and extensively absorbed from the tablets following oral administration; however, owing to extensive first-pass metabolism, bioavailability is low (approx. 30%) and large individual differences exist (11-52%). In one study, the administration of methylphenidate hydrochloride with food accelerated absorption, but had no effect on the amount absorbed.

Distribution

Peak plasma concentrations of 10.8 and 7.8 ng/mL were observed, on average, 2 hours after administration of 0.30 mg/kg in children and adults, respectively. Peak plasma concentrations showed marked variability between subjects. Both the area under the concentration-time curve (AUC), and the peak plasma concentrations (Cmax) showed dose-proportionality.

Elimination

Methylphenidate is eliminated from the plasma with a mean half-life of 2.4 hours in children and 2.1 hours in adults. The apparent mean systemic clearance after an oral dose is 10.2 and 10.5 L/h/kg in children and adults, respectively for a 0.3 mg/kg dose, and 0.565 L/h/kg after an intravenous dose of the racemate in healthy adult volunteers. These data indicate that the pharmacokinetics of methylphenidate in hyperactive children is similar to that in healthy adult volunteers. The apparent distribution volume of methylphenidate in children was approximately 20 L/kg, with substantial variability (11-33 L/kg). The volume of distribution after an intravenous dose (V_ss) is 2.23 L/kg for the racemate in healthy adult volunteers.

Following oral administration of methylphenidate, 78-97% of the dose is excreted in the urine and 1-3% in the feces in the form of metabolites within 48-96 hours. The main urinary metabolite is ritalinic acid (a-phenyl-2-piperidine acetic acid, PPAA); unchanged methylphenidate is excreted in the urine in small quantities (<1%). Peak PPAA plasma concentrations occurred at approximately the same time as peak methylphenidate concentrations, however, levels were several-fold greater than those of the unchanged drug. The half-life of PPAA was approximately twice that of methylphenidate.

In blood, methylphenidate and its metabolites are distributed between plasma (57%) and erythrocytes (43%). Methylphenidate and its metabolites exhibit low plasma protein binding (approx. 15%).

Methylphenidate excretion into breast milk has been noted in two case reports, where the calculated relative infant dose was ≤0.2% of the weight adjusted maternal dose.

Methylphenidate in the extended-release tablets is more slowly but as extensively absorbed as in the regular tablets. Relative bioavailability of the methylphenidate hydrochloride extended-release tablet, compared to the methylphenidate hydrochloride tablet, measured by the urinary excretion of the methylphenidate major metabolite (PPAA), was 105% (49-168%) in children and 101% (85%-152%) in adults. The time to peak rate in children was 4.7 hours (1.3-8.2 hours) for the extended-release tablets and 1.9 hours (0.3-4.4 hours) for the regular tablets. The elimination half-life and the cumulative urinary excretion of PPAA are not significantly different between the two dosage forms. An average of 67% of the extended-release tablet dose was excreted in children as compared to 86% in adults.

INDICATIONS AND CLINICAL USE

Sandoz Methylphenidate (methylphenidate hydrochloride) is indicated for the treatment of:

1. 1. Attention Deficit Hyperactivity Disorder (ADHD)

A diagnosis of ADHD (DSM-IV) implies the presence of hyperactive-impulsive or inattentive symptoms that caused impairment and that were present before age 7 years. The symptoms must be persistent, must be more severe than is typically observed in individuals at a comparable level of development, must cause clinically significant impairment, e.g., in social, academic, or occupational functioning, and must be present in 2 or more settings, e.g., school (or work) and at home. The symptoms must not be better accounted for by another mental disorder. For the Inattentive Type, at least 6 of the following symptoms must have persisted for at least 6 months: lack of attention to details/careless mistakes, lack of sustained attention, poor listener, failure to follow through on tasks, poor organization, avoids tasks requiring sustained mental effort, loses things, easily distracted, forgetful. For the Hyperactive-Impulsive Type, at least 6 of the following symptoms must have persisted for at least 6 months: fidgeting/squirming, leaving seat, inappropriate running/climbing, difficulty with quiet activities, “on the go”, excessive talking, blurting answers, can’t wait turn, intrusive. For a Combined Type diagnosis, both inattentive and hyperactive-impulsive criteria must be met.

Special Diagnostic Considerations

The specific etiology of ADHD is unknown, and there is no single diagnostic test. Adequate diagnosis requires the use not only of medical but of special psychological, educational, and social resources. Learning may or may not be impaired. The diagnosis must be based upon a complete history and evaluation of the patient and not solely on the presence of the required number of DSM-IV characteristics.

Need for Comprehensive Treatment Program

Sandoz Methylphenidate SR is indicated as an integral part of a total treatment program for ADHD that may include other measures (psychological, educational, social) for patients with this syndrome. Drug treatment may not be indicated for all patients with this syndrome. Drug treatment is not intended for use in the patient who exhibits symptoms secondary to environmental factors and/or other primary psychiatric disorders, including psychosis. Appropriate educational placement is essential in children and adolescents with this diagnosis and psychosocial intervention is often helpful. When remedial measures alone are insufficient, the decision to prescribe drug treatment medication will depend upon the physician’s assessment of the chronicity and severity of the patient’s symptoms.

Long-Term Use

The effectiveness of Sandoz Methylphenidate SR for long-term use, i.e. for more than 4 weeks has not been systematically evaluated in placebo-controlled trials. Therefore, the physician who elects to use Sandoz Methylphenidate SR for extended periods should periodically re-evaluate the long-term usefulness of the drug for the individual patient (see DOSAGE AND ADMINISTRATION).

1. 2. Narcolepsy

CONTRAINDICATIONS

Methylphenidate hydrochloride is contraindicated in the following conditions:

• Known or suspected hypersensitivity to the drug or to any of its excipients. For a complete listing, see the COMPOSITION section of the Product Monograph.
• Anxiety, tension.
• Agitation.
• Thyrotoxicosis.
• Advanced arteriosclerosis.
• Pre-existing cardiovascular disorders including moderate to severe hypertension, angina, arterial occlusive disease; heart failure, hemodynamically significant congenital heart disease, cardiomyopathies, myocardial infarction, potentially life-threatening arrhythmias and channelopathies (disorders caused by the dysfunction of ion channels).
• Glaucoma.
• Pheochromocytoma.
• Patients with motor tics and/or family history or diagnosis of Tourette's syndrome.
• During treatment with monoamine oxidase (MAO) inhibitors, and/or within a minimum of 14 days following discontinuation of those drugs, due to risk of hypertensive crises.

WARNINGS

Serious Warnings and Precautions

• Drug Dependence (see Dependence/Tolerance section below)

Cardiovascular

Sudden Death and Pre-existing Structural Cardiac Abnormalities or Other Serious Heart Problems

Children and Adolescents

Sudden death has been reported in association with stimulant drugs used for ADHD treatment at usual doses in children and adolescents with structural cardiac abnormalities or other serious cardiac problems. Although some serious heart problems alone carry an increased risk of sudden death, Methylphenidate hydrochloride generally should not be used in children, adolescents, or adults with known structural cardiac abnormalities (e.g., cardiomyopathy, serious heart rhythm abnormalities) or other serious cardiac problems that may increase vulnerability to the sympathomimetic effects of a stimulant drug.

Adults

Sudden deaths, stroke, and myocardial infarction have been reported in adults taking stimulant drugs at usual doses for ADHD. Although the role of stimulants in these adult cases is also unknown, adults have a greater likelihood than children of having serious structural cardiac abnormalities such as cardiomyopathy, serious heart rhythm abnormalities, coronary artery disease or other serious cardiac problems. Adults with such abnormalities should also generally not be treated with stimulant drugs (see CONTRAINDICATIONS).

General

Children: Theoretically there exists a pharmacological potential for all ADHD drugs to increase the risk of sudden/cardiac death. Although confirmation of an incremental risk for adverse cardiac events arising from treatment with ADHD medications is lacking, prescribers should consider this potential risk.

All drugs with sympathomimetic effects prescribed in the management of ADHD should be used with caution in patients who: a) are involved in strenuous exercise or activities, b) use ADHD drugs or c) have a family history of sudden/cardiac death. Prior to the initiation of treatment with sympathomimetic medications, a personal and family history (including assessment for a family history of sudden death or ventricular arrhythmia) and physical exam should be obtained to assess for the presence of cardiac disease. In patients with relevant risk factors and based on the clinician’s judgment, further cardiovascular evaluation may be considered (e.g., electrocardiogram and echocardiogram). Patients who develop symptoms such as exertional chest pain, unexplained syncope, or other symptoms suggestive of cardiac disease during ADHD treatment should undergo a prompt cardiac evaluation.

Misuse and Cardiovascular events

Misuse of stimulants of the CNS, including methylphenidate hydrochloride, may be associated with sudden death and other serious cardiovascular adverse events.

Hypertension and other Cardiovascular Conditions

Methylphenidate hydrochloride is contraindicated in patients with moderate to severe hypertension. Sympathomimetic medications can cause a modest increase in average blood pressure and average heart rate and individuals may have larger increases. While the mean changes alone would not be expected to have short-term consequences, all patients should be monitored for larger changes in heart rate and blood pressure. Caution is indicated in treating patients whose underlying medical conditions might be compromised by increases in blood pressure or heart rate, e.g., those with pre-existing hypertension (see also WARNINGS and CONTRAINDICATIONS).

Cerebrovascular

Cerebrovascular conditions

Patients with pre-existing CNS abnormalities, e.g., cerebral aneurysm and/or other vascular abnormalities such as vasculitis or pre-existing stroke should not be treated with methylphenidate hydrochloride. Patients with additional risk factors (history of cardiovascular disease, concomitant medications that elevate blood pressure) should be assessed regularly for neurological/psychiatric signs and symptoms after initiating treatment with methylphenidate hydrochloride (see above, Cardiovascular, and PRECAUTIONS, Drug Interactions).

Dependence/Tolerance

Drug Dependence: Methylphenidate hydrochloride should be given cautiously to emotionally unstable patients, such as those with a history of drug dependence or alcoholism, because such patients may increase dosage on their own initiative.

Chronically abusive use can lead to marked tolerance and psychological dependence with varying degrees of abnormal behaviour. Frank psychotic episodes can occur, especially with parenteral abuse. Careful supervision is required during drug withdrawal, since severe depression may occur. Withdrawal following chronic therapeutic use may unmask symptoms of an underlying disorder that may require follow-up.

Clinical data indicate that treatment with methylphenidate hydrochloride during childhood and/or adolescence does not seem to result in increased predisposition for addiction.

Endocrine and Metabolism

Long-Term Suppression of Growth

Suppression of growth (i.e., weight gain and/or height) has been reported with the long-term use of stimulants, including methylphenidate hydrochloride, in children (see ADVERSE REACTIONS). Growth should be monitored as clinically necessary during treatment with methylphenidate hydrochloride, and patients who are not growing or gaining height or weight as expected may need to have their treatment interrupted. In addition, the use of "Drug Holidays" is recommended, that is, withholding the drug on weekends and during school holidays in a smuch as the clinical situation permits.

Fatigue

Methylphenidate hydrochloride should not be used for the prevention or treatment of normal fatigue states.

Neurologic

Seizures

There is some clinical evidence that methylphenidate hydrochloride may lower the convulsive threshold in patients with prior history of seizures, with prior EEG abnormalities in absence of seizures and, very rarely, in patients with no prior EEG evidence or history of seizures. Clinical experience has shown that a small number of patients may experience an increase in seizure frequency when treated with methylphenidate hydrochloride. If seizure frequency rises, the drug should be discontinued.

Ophthalmologic

Visual Disturbance

Symptoms of visual disturbances have been encountered in rare cases. Difficulties with accommodation and blurring of vision have been reported.

Psychiatric conditions

Co-morbidity of psychiatric disorders in ADHD is common and should be taken into account when prescribing stimulant products. Prior to initiating treatment with methylphenidate hydrochloride, patients should be assessed for pre-existing and/or a family history of psychiatric disorders (see DOSAGE AND ADMINISTRATION).

Treatment of ADHD with stimulant products including methylphenidate hydrochloride should not be initiated in patients with acute psychosis, acute mania or acute suicidality. These acute conditions should be treated and controlled before ADHD treatment is considered.

Pre-Existing Psychosis

Administration of stimulants may exacerbate symptoms of behaviour disturbance and thought disorder in patients with a pre-existing psychotic disorder.

Screening Patients for Bipolar Disorder

Particular care should be taken in using stimulants to treat ADHD in patients with comorbid bipolar disorder because of concern for possible induction of a mixed/manic episode in such patients. Prior to initiating treatment with a stimulant, patients with comorbid depressive symptoms should be adequately screened to determine if they are at risk for bipolar disorder; such screening should include a detailed psychiatric history, including a family history of suicide, bipolar disorder, and depression.

Emergence of New Psychotic or Manic Symptoms

Treatment emergent psychotic or manic symptoms, e.g., hallucinations, delusional thinking, or mania in children and adolescents without a prior history of psychotic illness or mania, can be caused by stimulants at usual doses. If such symptoms occur, consideration should be given to a possible causal role of the stimulant, and discontinuation of treatment may be appropriate. In a pooled analysis of multiple short-term, placebo-controlled studies, such symptoms occurred in about 0.1% (4 patients with events out of 3482 exposed to methylphenidate or amphetamine for several weeks at usual doses) of stimulant-treated patients compared to 0 in placebo-treated patients.

Aggression

Aggressive behaviour or hostility is often observed in children and adolescents with ADHD, and has been reported in clinical trials and the postmarketing experience of some medications indicated for the treatment of ADHD. Although there is no systematic evidence that stimulants cause aggressive behaviour or hostility, patients beginning treatment for ADHD should be monitored for the appearance of or worsening of aggressive behaviour or hostility.

Suicidal Behaviour and Ideation

There have been post-marketing reports of suicide-related events in patients treated with ADHD drugs, including cases of ideation, attempts, and very rarely, completed suicide. The mechanism of this risk is not known. ADHD and its related co-morbidities may be associated with increased risk of suicidal ideation and/or behaviour.

Therefore, it is recommended for patients treated with ADHD drugs that caregivers and physicians monitor for signs of suicide-related behaviour, including at dose initiation/optimization and drug discontinuation. Patients should be encouraged to report any distressing thoughts or feelings at any time to their healthcare professional. Patients with emergent suicidal ideation and behaviour should be evaluated immediately. The physician should initiate appropriate treatment of the underlying psychiatric condition and consider a possible change in the ADHD treatment regimen (see ADVERSE REACTIONS, Post-Market Adverse Drug Reactions).

Depression

Methylphenidate hydrochloride should not be used to treat severe exogenous or endogenous depression.

Tics

Methylphenidate hydrochloride is associated with the onset or exacerbation of motor and verbal tics. Worsening of Tourette’s syndrome has also been reported (see ADVERSE REACTIONS). Family history should be assessed and clinical evaluation for tics or Tourette’s syndrome in children should precede use of methylphenidate for ADHD treatment. Methylphenidate hydrochloride is contraindicated in case of diagnosis or family history of Tourette's syndrome (see CONTRAINDICATIONS). Patients should be regularly monitored for the emergence or worsening of tics during treatment with methylphenidate hydrochloride.

Serotonin syndrome

Serotonin syndrome is a rare but potentially life-threatening condition resulting from concomitant administration of serotonergic drugs. Serotonin syndrome has been reported when methylphenidate was co-administered with serotonergic drugs such as selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs). Other common serotonergic drugs include: tricyclic antidepressants (TCAs), monoamine oxidase inhibitors (MAOIs), serotonin 5-HT1 receptor agonists (triptans), and 5-HT3 receptor antagonist antiemetics. The concomitant use of methylphenidate and serotonergic drugs is not recommended as this may lead to the development of serotonin syndrome. The symptoms of serotonin syndrome may include mental status changes (e.g., agitation, hallucinations, delirium, and coma), autonomic instability (e.g., tachycardia, labile blood pressure, dizziness, diaphoresis, flushing, hyperthermia), neuromuscular symptoms (e.g., tremor, rigidity, myoclonus, hyperreflexia, incoordination), seizures, and/or gastrointestinal symptoms (e.g., nausea, vomiting, diarrhea). Prompt recognition of these symptoms is important so that treatment with methylphenidate and serotonergic drugs can be immediately discontinued and appropriate treatment instituted (see DRUG INTERACTIONS).

Sexual Function/Reproduction

Priapism

Prolonged and painful erections requiring immediate medical attention (sometimes including surgical intervention), have been reported with methylphenidate products, including Sandoz Methylphenidate SR in both pediatric and adult patients (see ADVERSE REACTIONS, Post-Market Adverse Drug Reactions). Priapism can develop after some time on methylphenidate, often subsequent to an increase in dose. Priapism has also appeared during a period of methylphenidate withdrawal (drug holidays or during discontinuation). Patients who develop abnormally sustained erections or frequent and painful erections should seek immediate medical attention.

Vascular

Peripheral Vasculopathy, Including Raynaud’s Phenomenon

Stimulants used to treat ADHD, such as methylphenidate hydrochloride, are associated with peripheral vasculopathy, including Raynaud’s phenomenon. Signs and symptoms are usually intermittent and mild; however, very rare sequelae include digital ulceration and/or soft tissue breakdown. Effects of peripheral vasculopathy, including Raynaud’s phenomenon, were observed in post-marketing reports at different times and at therapeutic doses in all age groups throughout the course of treatment. Signs and symptoms generally improve after reduction in dose or discontinuation of drug. Careful observation for digital changes is necessary during treatment with ADHD stimulants. Further clinical evaluation (e.g., rheumatology referral) may be appropriate for certain patients.

Special populations

Pregnant women: There is limited experience with use of methylphenidate in pregnant women. Methylphenidate hydrochloride has been shown to have teratogenic effects in rabbits when given in doses of 200 mg/kg/day.

Cases of neonatal cardiorespiratory toxicity, specifically fetal tachycardia and respiratory distress have been reported in spontaneous reports.

Therefore, methylphenidate hydrochloride should not be given to pregnant women unless the potential benefit outweighs the risk to fetus.

Nursing women: Case reports showed that methylphenidate was distributed into breast milk reaching a milk-to-plasma ratio of approximately 2.5 (see ACTION AND CLINICAL PHARMACOLOGY).

There is one case report of an infant who experienced an unspecified decrease in weight during the period of exposure but recovered and gained weight after the mother discontinued treatment with methylphenidate. A risk to the suckling child cannot be excluded. A decision should be made whether to abstain from breast-feeding or to abstain from methylphenidate hydrochloride therapy, taking into account the benefit of breast-feeding to the child and the benefit of therapy to the woman.

Use in Children Under Six Years of Age

Methylphenidate hydrochloride should not be used in children under 6 years of age, since safety and efficacy in this age group have not been established.

PRECAUTIONS

Patients with an element of agitation may react adversely; discontinue therapy if necessary.

Drug treatment is not indicated in all cases of ADHD and should be considered only in light of the complete history and evaluation of the child. The decision to prescribe methylphenidate hydrochloride should depend on the physician's assessment of the chronicity and severity of the child's symptoms and their appropriateness for his/her age. Prescription should not depend solely on the presence of one or more abnormal behavioural characteristics. Where these symptoms are associated with acute stress reactions, treatment with methylphenidate hydrochloride is usually not indicated.

Hematological effects

Long-term effects of methylphenidate hydrochloride in children have not been well established.

Periodic CBC, differential, and platelet counts are advised during prolonged therapy. In the event of hematological disorders appropriate medical intervention should be considered (see ADVERSE REACTIONS).

Driving and using machines

Methylphenidate hydrochloride may cause dizziness, drowsiness, blurred vision, hallucinations or other CNS side effects (see ADVERSE REACTIONS). Patients experiencing such side effects should refrain from driving, operating machinery, or engaging in other potentially hazardous activities.

DRUG INTERACTIONS

Pharmacodynamic interactions

Anti-hypertensive drugs

Methylphenidate hydrochloride may decrease the effectiveness of drugs used to treat hypertension.

Use with drugs that elevate blood pressure

Use with caution in patients being treated with drugs that elevate blood pressure (see also WARNINGS, Cerebrovascular Conditions).

Because of possible hypertensive crisis, methylphenidate hydrochloride is contraindicated in patients being treated (currently or within the preceding 14 days) with MAO-inhibitors (see CONTRAINDICATIONS).

Use with anesthetics

With halogenated anesthetics, there is a risk of sudden blood pressure and heart rate increase during surgery. Methylphenidate may also antagonize the sedative effect of general anesthetics. If surgery is planned, methylphenidate hydrochloride should not be taken on the day of surgery.

Use with centrally acting alpha-2 agonists (e.g., clonidine)

Serious adverse events including sudden death have been reported in concomitant use with clonidine. In these cases, no causality for the combination could be established because of insufficient data.

Use with dopaminergic drugs

As an inhibitor of dopamine reuptake, methylphenidate hydrochloride may be associated with pharmacodynamic interactions when co-administered with direct and indirect dopamine agonists (including DOPA and tricyclic antidepressants) as well as dopamine antagonists (antipsychotics, e.g. haloperidol). The co-administration of methylphenidate hydrochloride with antipsychotics is not recommended because of the counteracting mechanism of action.

Use with alcohol

Alcohol may exacerbate the adverse CNS effect of psychoactive drugs, including methylphenidate hydrochloride. Therefore, patients should be advised to abstain from alcohol during treatment.

Use with serotonergic drugs

The concomitant use of methylphenidate and serotonergic drugs is not recommended as this may lead to the development of serotonin syndrome (see WARNINGS). Methylphenidate has been shown to increase extracellular serotonin and norepinephrine and appears to have weak potency in binding serotonin transporter.

Pharmacokinetic interactions

Methylphenidate hydrochloride is not metabolized by cytochrome P450 to a clinically relevant extent. Inducers or inhibitors of cytochrome P450 are not expected to have any relevant impact on methylphenidate hydrochloride pharmacokinetics. Conversely, the d- and l- enantiomers of methylphenidate in methylphenidate hydrochloride did not relevantly inhibit cytochrome P450 1A2, 2C8, 2C9, 2C19, 2D6, 2E1 or 3A.

Methylphenidate hydrochloride co-administration did not increase plasma concentrations of the CYP2D6 substrate desipramine.

Case reports suggested a potential interaction of methylphenidate hydrochloride with coumarin anticoagulants, some anticonvulsants (e.g., phenobarbital, diphenylhydantoin, primidone), phenylbutazone and tricyclic antidepressants but pharmacokinetic interactions were not confirmed when explored at larger sample sizes. Downward dosage adjustments of these drugs might be required when given concomitantly with methylphenidate hydrochloride.

An interaction with the anticoagulant ethylbiscoumacetate in 4 subjects was not confirmed in a subsequent study with a larger sample size (n=12).

Other specific drug-drug interaction studies with methylphenidate hydrochloride have not been performed in vivo.

Drug-laboratory test

Methylphenidate may induce false positive laboratory tests for amphetamines, particularly with immunoassays screen test.

ADVERSE REACTIONS

Adverse drug reactions are listed by MedDRA-based system organ class. Within each system organ class, the adverse drug reactions are ranked by frequency, with the most frequent reactions first. Within each frequency grouping, adverse drug reactions are presented in order of decreasing seriousness. In addition, the corresponding frequency category is based on the following convention (CIOMS III): very common ≥10 %, common ≥ 1% to < 10%; uncommon ≥ 0.1 % to < 1%; rare ≥ 0.01% to < 0.1 %; very rare < 0.01 %.

Nervousness and insomnia are very common adverse reactions, which occur at the beginning of methylphenidate hydrochloride treatment, but can usually be controlled by reducing dosage and/or omitting the afternoon or evening dose.

Decreased appetite is also very common but usually transient. Abdominal pain, nausea and vomiting are common to very common, usually occur at the beginning of treatment and may be alleviated by concomitant food intake.

Psychiatric

Very common: nervousness, insomnia.

Common: anxiety, restlessness, sleep disorder, agitation.

Very rare: hyperactivity, psychosis (sometimes with visual and tactile hallucinations), transient depressed mood.

Central and Peripheral Nervous System

Common: dyskinesia, tremor, headache, drowsiness, dizziness.

Very rare: convulsions, choreoathetoid movements, tics, or exacerbation of existing tics and Tourette's syndrome, cerebrovascular disorders including vasculitis, cerebral hemorrhages and cerebrovascular accidents.

Eye disorders

Rare: Symptoms of visual disturbances, difficulties in visual accommodation and blurred vision.

Respiratory, Thoracic and mediastinal disorders

Common: cough.

Gastrointestinal System

Very common: nausea, dry mouth.

Common: abdominal pain, vomiting, dyspepsia, toothache. Hepatobiliary disorders

Very rare: abnormal liver function, ranging from transaminase elevation to hepatic coma.

Cardiac disorders

Common: palpitations, changes in blood pressure and heart rate (usually an increase), tachycardia, cardiac arrhythmias.

Rare: angina pectoris.

Skin and subcutaneous tissue disorders

Common: rash, pruritus, urticaria, fever, scalp hair loss, hyperhidrosis.

Very rare: exfoliative dermatitis, erythema multiforme, thrombocytopenic purpura.

Musculoskeletal and connective tissue disorders

Common: arthralgia.

Very rare: muscle cramps.

Immune system disorders

Very rare: hypersensitivity reactions, including angioedema and anaphylaxis.

Infections and infestations

Very common: nasopharyngitis.

Blood and the lymphatic system disorders

Very rare: leucopenia, thrombocytopenia, anemia.

Metabolism and nutrition disorders

Very common: decreased appetite.

Rare: moderately reduced weight gain during prolonged use in children.

General disorders and administration site conditions

Common: feeling jittery.

Rare: slight growth retardation during prolonged use in children.

Investigations

Common: weight decreased.

In children, loss of appetite, abdominal pain, weight decrease, insomnia, and tachycardia may occur more frequently; however, any of the other adverse reactions listed above may also occur.

Very rare reports of poorly documented neuroleptic malignant syndrome (NMS) have been received. In most of these reports, patients were also receiving other medications. It is uncertain what role methylphenidate hydrochloride played in these cases.

Post-Market Adverse Drug Reactions

Adverse events reported since market introduction in patients taking methylphenidate hydrochloride include sudden cardiac death, Stevens-Johnson Syndrome, pancreatitis, Raynaud’s phenomenon, aplastic anaemia, hypoglycaemia, and transient pancytopenia.

Suicidal Behaviour and Ideation

There have been post-marketing reports of suicide-related events, including completed suicide, suicide attempt, and suicidal ideation in patients treated with ADHD drugs. In some of these reports, comorbid conditions may have contributed to the event. (See WARNINGS, Suicidal Behaviour and Ideation)

Priapism

Priapism has been reported with methylphenidate products including Sandoz Methylphenidate SR (See WARNINGS AND PRECAUTIONS).

Adverse Events with Other Methylphenidate Hydrochloride Products

Nervousness and insomnia are the most common adverse reactions reported with other methylphenidate products. Other reactions include hypersensitivity (including skin rash, urticaria, fever, arthralgia, exfoliative dermatitis, erythema multiforme with histopathological findings of necrotizing vasculitis, and thrombocytopenic purpura); anorexia; nausea; dizziness; headache; dyskinesia; drowsiness; blood pressure and pulse changes, both up and down; tachycardia; angina; abdominal pain; weight loss during prolonged therapy. There have been rare reports of Tourette’s syndrome. Toxic psychosis has been reported. Although a definite causal relationship has not been established, the following have been reported in patients taking this drug: instances of abnormal liver function, e.g., hepatic coma; isolated cases of cerebral arteritis and/or occlusion; leukopenia and/or anaemia; transient depressed mood; a few instances of scalp hair loss. Very rare reports of NMS have been received, and in most of these, patients were concurrently receiving therapies associated with NMS. In a single report, a ten-year-old boy who had been taking methylphenidate for approximately 18 months experienced an NMS-like event within 45 minutes of ingesting his first dose of venlafaxine. It is uncertain whether this case represented a drug-drug interaction, a response to either drug alone, or some other cause.

The list below shows adverse reactions that have been reported with other methylphenidate-containing products based on clinical trials data and post-marketing spontaneous reports:

Psychiatric disorders: Irritability, aggression, affect lability, abnormal behaviour or thinking, anger, mood altered, mood swings, hypervigilance, mania, disorientation, libido disorder, apathy, repetitive behaviours, over-focusing, confusional state, dependence, cases of abuse and dependence have been described, more often with immediate release formulations.

Nervous system disorders: Reversible ischemic neurological deficit, migraine.

Eye disorders: Diplopia, mydriasis.

Cardiac disorders: Cardiac arrest, myocardial infarction.

Vascular disorders: Peripheral coldness

Respiratory, thoracic and mediastinal disorders: Pharyngolaryngeal pain, dyspnea

Gastrointestinal disorders: Diarrhea, constipation.

Skin and subcutaneous tissue disorders: Angioneurotic oedema, erythema, fixed drug eruption.

Musculoskeletal, connective tissue and bone disorders: Myalgia, muscle twitching, rhabdomyolysis.

Renal and urinary disorders: Hematuria.

Reproductive system and breast disorders: Gynecomastia.

General disorders and administration site conditions: Chest pain, fatigue.

Investigations: Cardiac murmur.

SYMPTOMS AND TREATMENT OF OVERDOSAGE

For management of a suspected drug overdose, contact your regional Poison Control Centre.

Signs and symptoms of acute overdosage, resulting principally from overstimulation of the CNS and from excessive sympathomimetic effects, may include the following: vomiting, agitation, tremors, hyperreflexia, muscle twitching, convulsions (may be followed by coma), euphoria, confusion, hallucinations, delirium, sweating, flushing, headache, hyperpyrexia, tachycardia, palpitations, cardiac arrhythmias, hypertension, mydriasis, dryness of mucous membranes and rhabdomyolysis

Management consists in providing supportive measures, and symptomatic treatment of life-threatening events, e.g. hypertensive crisis, cardiac arrhythmias, convulsions. For the most current guidance for treatment of symptoms of overdose, the practitioner should consult a certified Poison Control Center or current toxicological publication.

Supporting measures include preventing self-injury and protecting the patient from external stimuli that would exacerbate the overstimulation already present. If the overdose is oral and the patient is conscious, gastric contents could be evacuated by induction of emesis, followed by administration of activated charcoal. Airway protected gastric lavage is necessary in hyperactive or unconscious patients, or those with depressed respiration.

Intensive care must be provided to maintain adequate circulation and respiratory exchange; external cooling procedures may be required to reduce hyperpyrexia.

Efficacy of peritoneal dialysis or extracorporeal hemodialysis for methylphenidate hydrochloride overdosage has not been established.

DOSAGE AND ADMINISTRATION

Dosing Considerations

Sandoz Methylphenidate SR should be administered starting at the lowest possible dose; dosage should then be individually and slowly adjusted to the lowest effective dosage since individual patient response to methylphenidate varies widely.

Sandoz Methylphenidate SR should not be used in patients with pre-existing cardiovascular disorders and should generally not be used in patients with known structural cardiac abnormalities (see CONTRAINDICATIONS and WARNINGS).

Children: Theoretically, there exists a pharmacological potential for all ADHD drugs to increase the risk of sudden/cardiac death. Although confirmation of an incremental risk for adverse cardiac events arising from treatment with ADHD medications is lacking, prescribers should consider this potential risk.

All drugs with sympathomimetic effects prescribed in the management of ADHD should be used with caution in patients who: a) are involved in strenuous exercise or activities b) use stimulants or

1. c) have a family history of sudden/cardiac death. Prior to the initiation of treatment with sympathomimetic medications, a personal and family history (including assessment for a family history of sudden death or ventricular arrhythmia) and physical exam should be obtained to assess for the presence of cardiac disease. In patients with relevant risk factors and based on the clinician’s judgment, further cardiovascular evaluation may be considered (e.g., electrocardiogram and echocardiogram). Patients who develop symptoms such as exertional chest pain, unexplained syncope, or other symptoms suggestive of cardiac disease during ADHD treatment should undergo a prompt cardiac evaluation.

Patients who are considered to need extended treatment with methylphenidate should undergo periodic evaluation of their cardiovascular status (See WARNINGS).

Before initiating Sandoz Methylphenidate SR treatment, patients should be assessed for pre-existing and/or family history of psychiatric disorders (see WARNINGS). Caution should be exercised in prescribing concomitant drugs.

Recommended Dose and Dosage Adjustment

General

Dosage of Sandoz Methylphenidate SR should be individualized according to the needs and responses of the patient.

Dose Titration and Maintenance/Extended Treatment

Children and adolescents (6 Years and Over)

Sandoz Methylphenidate Tablets: Sandoz Methylphenidate Tablets should be initiated in small doses, (e.g., 5-10 mg TID) with weekly increments of 5 to 10 mg in the daily dosage. Dosage should be individualized on the basis of factors such as age, body weight and individual response. Timing of drug administration should be aimed to coincide with periods of greatest academic, behavioural and social stress.

Sandoz Methylphenidate SR (extended-release) Tablets: Sandoz Methylphenidate SR tablets have a duration of action of approximately 8 hours. Therefore, Sandoz Methylphenidate SR tablets may be used in place of methylphenidate hydrochloride tablets when the 8-hour dosage of Sandoz Methylphenidate SR corresponds to the titrated 8-hour dosage of methylphenidate hydrochloride.

Adults

Sandoz Methylphenidate Tablets: Administer in divided doses 2 or 3 times daily. Average daily dosage is 20 to 30 mg. Some patients may require 40 to 60 mg daily. In others, 10 to 15 mg daily will be adequate. Patients who are unable to sleep if medication is taken late in the day, should take the last dose before 6 p.m.

Sandoz Methylphenidate SR (extended-release) Tablets: Sandoz Methylphenidate SR tablets have a duration of action of approximately 8 hours. Therefore, Sandoz Methylphenidate SR tablets may be used in place of methylphenidate hydrochloride tablets when the 8-hour dosage of Sandoz Methylphenidate SR corresponds to the titrated 8-hour dosage of methylphenidate hydrochloride.

Daily dosage above 60 mg is not recommended.

Dose Reduction and Discontinuation

If symptoms do not improve after dose titration over a one month period, the drug should be discontinued.

If symptoms worsen or other adverse events occur, the dosage should be reduced or, if necessary, the drug discontinued.

If paradoxical aggravation of symptoms or other adverse effects occur, reduce dosage, or if necessary, discontinue the drug.

Methylphenidate hydrochloride should be periodically discontinued to assess the child's condition. Improvement may be sustained when the drug is either temporarily or permanently discontinued.

Drug treatment should not and need not be indefinite and usually may be discontinued after puberty.

Administration

Sandoz Methylphenidate SR Tablets are administered orally and can be taken with or without food (see ACTION AND CLINICAL PHARMACOLOGY). Sandoz Methylphenidate SR tablets must be swallowed whole and never be crushed or chewed.

Special populations

Renal impairment

No studies have been performed in renally impaired patients.

Hepatic impairment

No studies have been performed in hepatically impaired patients.

Geriatric patients

No studies have been performed in patients over 60 years of age.

PHARMACEUTICAL INFORMATION

Drug Substance

Structural formula:

COMPOSITION

Sandoz Methylphenidate (methylphenidate hydrochloride) 10 mg Tablets

Each tablet contains medicinal ingredient methylphenidate hydrochloride and non-medicinal ingredients: corn starch, FD&C Green No. 3, lactose, magnesium stearate, polyethylene glycol, sugar and talc.

Sandoz Methylphenidate (methylphenidate hydrochloride) 20 mg Tablets

Each tablet contains the medicinal ingredient methylphenidate hydrochloride and non-medicinal ingredients: D&C Yellow No. 10, lactose, magnesium stearate, polyethylene glycol, sugar, tragacanth and talc.

Sandoz Methylphenidate (methylphenidate hydrochloride) 20 mg SR Tablets

Each tablet contains the medicinal ingredient methylphenidate hydrochloride and non-medicinal ingredients: cellulose compounds, cetostearyl alcohol, castor oil compounds, lactose, magnesium stearate, talc and titanium dioxide.

STORAGE AND STABILITY

Protect from heat (store between 2 and 30°C) and humidity.

Keep out of reach and sight of children.

DOSAGE FORMS AND PACKAGING

Sandoz Methylphenidate (methylphenidate hydrochloride) Tablets 10 mg

Pale blue, round, flat-faced, beveled-edged tablets that are scored and imprinted "AB" on one side.

Sandoz Methylphenidate (methylphenidate hydrochloride) Tablets 20 mg

Pale yellow, round, flat-faced, beveled-edged tablets that are scored and imprinted "PN" on one side.

Sandoz Methylphenidate SR 20 mg (methylphenidate hydrochloride extended-release tablets)

White, round, biconvex, beveled edge, film coated tablets, printed “SZ” on one side and “20” on the other side in black ink.

Sandoz Methylphenidate 10 mg tablets are packaged in bottles of 100.

Sandoz Methylphenidate 20 mg tablets are packaged in bottles of 100.

Sandoz Methylphenidate SR 20 mg tablets are packaged in bottles of 100. Sandoz Methylphenidate SR is a controlled drug (Schedule G).

TOXICOLOGY

Reproductive toxicity

Methylphenidate hydrochloride has been shown to have teratogenic effects in rabbits when given in doses of 200 mg/kg/day. Spina bifida with malrotated hind limb was observed in 2 (out of 18) litters. The no effect level for embryofetal development in rabbits was 60 mg/kg/day (11 times the maximum recommended human dose [MRHD] on a mg/m² basis).

When methylphenidate was administered to rats throughout pregnancy and lactation at doses of up to 45 mg/kg/day (4 times the MRHD on a mg/m² basis), offspring body weight gain was decreased at the highest dose, but no other effects on postnatal development were observed.

Carcinogenesis-mutagenesis

In a lifetime carcinogenicity study carried out in B6C3F1 mice, methylphenidate caused an increase in hepatocellular adenomas and, in males only, an increase in hepatoblastomas, at a daily dose of approximately 60 mg/kg/day. This dose is approximately 30 times and 2.5 times the maximum recommended human dose on a mg/kg and mg/m² basis, respectively. Hepatoblastoma is a relatively rare rodent malignant tumor type. There was no increase in total malignant hepatic tumors. The mouse strain used is sensitive to the development of hepatic tumors, and the significance of these results to humans is unknown.

The US Food and Drugs Administration examined data from the Surveillance, Epidemiology and End Results (SEER) database for the years 1973 to 1991 and found that the estimated incidence of hepatoblastoma in the general population was not greater than 1 in 10 million person years.

A total of 174 cases of hepatoblastoma were reported by the SEER for the period 1973 to 1995. Age-adjusted incidence rate was very low (IR=0,0382 per 100,000 person years). The majority of cases (149 out of 174) were diagnosed among the age group 0 to 4 years old, which is in accordance with the natural history of the disease. For the age group 5 to 24 years old the rates of hepatoblastoma were very low with few or no cases reported.

On the basis of experience since marketing methylphenidate hydrochloride, there is no evidence that the incidence is higher in patients receiving methylphenidate hydrochloride.

Methylphenidate did not cause any increases in tumors in a lifetime carcinogenicity study carried out in F344 rats; the highest dose used was approximately 45 mg/kg/day, which is approximately 22 times and 4 times the maximum recommended human dose on a mg/kg and mg/m² basis, respectively.

Methylphenidate was not mutagenic in the in vitro Ames reverse mutation assay or in the in vitro mouse lymphoma cell forward mutation assay. Sister chromatid exchanges and chromosome aberrations were increased, indicative of a weak clastogenic response in an in vitro assay in Chinese Hamster Ovary (CHO) cells. In an in vivo study of the effect of methylphenidate on bone marrow cells (micronucleus test) there was no evidence of clastogenic or aneugenic effects in mice, at doses up to 250 mg/kg.

Juvenile neurobehavioural development

Repeated oral administration of methylphenidate to young rats identified decreased spontaneous locomotor activity at 50 mg/kg/day, due to an exaggerated pharmacological activity of methylphenidate. The systemic exposure in young rats at this dose is 3.4 (male) and 18 (female) times that in children at the maximum recommended human dose (60 mg). In female rats, a deficit in the acquisition of a specific learning task was also observed at the dose of 100 mg/kg/day (the systemic exposure in young female rat at that dose is 28.5 times that in children at the maximum recommended human dose). The clinical relevance of these findings is unknown.

REFERENCES

1. 1. Bakhtiar R, and Tse FL. Toxicokinetic assessment of methylphenidate (Ritalin) enantiomers in pregnant rats and rabbits. Biomed Chromatogr. 2004;18: 275-81.
2. 2. Beck L, et al. Childhood chemotherapy and later drug abuse and growth curve: A follow-up study of 30 adolescents. Am J Psychiatry 1975; 132: 436-438.
3. 3. CANADIAN PAEDIATRIC SOCIETY, MENTAL HEALTH COMMITTEE. Use of methylphenidate for attention deficit hyperactivity disorder. Can Med Assoc J 1990; 142: 817-818.
4. 4. Douglas VI, et al. Dosage effects and individual responsivity to methylphenidate in attention deficit disorder in the laboratory and in the classroom. J Child Psychol Psychiatry 1988; 29: 453-475.
5. 5. Douglas VI, et al. Short-term effects of methylphenidate on the cognitive, learning and academic performance of children with attention deficit disorder in the laboratory and in the classroom. J Child Psychol Psychiatry 1985; 27: 191-211.
6. 6. Gittelman KR, and Mannuzza S. Hyperactive boys almost grown up. III. Methylphenidate effects on ultimate height. Arch Gen Psychiatry (USA) 1988; 45: 1131-1134.
7. 7. Hoffmann BB, Lefkowitz RJ. Cathecholamines, sympatheomimetic drugs, and adrenergic receptor antagonists. In: Hardman JG, Limbird LE, Moniloff PB, et al., eds. Goodman and Gilman's The Pharmacological Basis of Therapeutics. -9th ed. New York, NY: McGraw-Hill Inc; 1996: 219-221.
8. 8. Golinko BE. Side effects of dextroamphetamine and methylphenidate in hyperactive children
9. - A brief review. Prog Neuropsychopharmacol Biol Psychiatry 1984; 8: 1-8.
10. 9. Hechtman L, et al. Young adult outcome of hyperactive children who received long-term stimulant treatment. J Am Acad Child Psychiatry 1984; 23: 261-269.
11. 10. Hesterly SO. Clinical management of children with hyperactivity. A shift in diagnostic and therapeutic emphasis. Postgrad Med 1986; 79: 299-305.
12. 11. Hungund BL, et al. Pharmacokinetics of methylphenidate in hyperkinetic children. Br J Clin Pharmacol 1979; 8: 571-576.
13. 12. Honda Y, et al. Long-term treatment of narcolepsy with methylphenidate (RITALIN*). Curr Ther Res 1979; 25: 288-298.
14. 13. Leary PM, et al. Clinical experience with methylphenidate. S Afr Med J 1979; 55: 374-376.
15. 14. Olson KR. Poisoning and Drug Overdose -46th ed. 2004. McGraw-Hill, p. 72-73.
16. 15. Redalieu E, et al. A study of methylphenidate in man with respect to its major metabolite.Drug Metab Dispos 1982; 10: 708-709.
17. 16. Shaywitz SE, et al. Psycho-pharmacology of attention deficit disorder: pharmacokinetic, neuro-endocrine and behavioural measures following acute and chronic treatment with methylphenidate. Pediatrics 1982: 69: 688-694.
18. 17. Suter W, et al. Methylphenidate is not clastogenic in cultured human lymphocytes and in the mouse bone-marrow micronucleus test. Mutat Res 2006; 607:153-159.
19. 18. Taylor E, et al. Which boys respond to stimulant medication? A controlled trial of methylphenidate in boys with disruptive behaviour. Psychol Med 1987; 17: 121-143.
20. 19. Topol EJ, et al. (Eds) Textbook of Cardiovascular Medicine-2nd ed. 2002. Lippincott Williams and Williams P. 874.
21. 20. Wargin W, et al. Pharmacokinetics of methylphenidate in man, rat and monkey. J Pharmacol Exp Ther 1983; 226: 382-386.
22. 21. Weiss G, et al. Comparison of the effects of chlorpromazine, dextro-amphetamine and methylphenidate on the behaviour and intellectual functioning of hyperactive children. Can Med Assoc J 1971; 104: 20-25.
23. 22. Whitehouse D, et al. Comparison of sustained-release and standard methylphenidate in the treatment of minimal brain dysfunction. J Clin Psychiatry 1980; 41: 282-28.
24. 23. Novartis Pharmaceuticals Canada Inc., RITALIN^® SR Tablets Product Monograph, Control No.208313, Revision date: November 8, 2017.