Nat-Ondansetron: Uses, Side Effects and Dosage

What is NAT-ONDANSETRON used for?

Children (4 to 17 years of age):

NAT-ONDANSETRON is used to treat nausea and vomiting during certain types of chemotherapy.

Adults (18 to 64 years of age):

NAT-ONDANSETRON is used:

• to prevent nausea and vomiting during certain types of chemotherapy and radiotherapy, and
• to prevent nausea and vomiting after surgery.

Geriatrics (65 years of age and older):

NAT-ONDANSETRON is used to prevent nausea and vomiting during chemotherapy and radiotherapy.

How does NAT-ONDANSETRON work?

NAT-ONDANSETRON is a medication known as an antiemetic. Treatments such as cancer chemotherapy and radiotherapy are associated with the release of a natural substance (serotonin). The release of serotonin, can make you feel sick and vomit. The way that NAT-ONDANSETRON works is not known, but it is thought to help stop the effects of serotonin to reduce the effects of nausea and vomiting.

What are the ingredients in NAT-ONDANSETRON?

Medicinal ingredient: ondansetron hydrochloride dihydrate

Non-medicinal ingredients: croscarmellose sodium, , ferric oxide yellow, hypromellose (E5), lactose monohydrate, magnesium stearate, microcrystalline cellulose, pregelatinized starch, titanium dioxide, triacetin.

NAT-ONDANSETRON comes in the following dosage forms:

NAT-ONDANSETRON (Tablets)

Tablets: 4 mg and 8 mg of ondansetron (as ondansetron hydrochloride dihydrate).

Do not use NAT-ONDANSETRON if:

• you are allergic to ondansetron hydrochloride dihydrate, or to any other ingredients in NAT-ONDANSETRON.
• you are taking a medicine called apomorphine (used to treat Parkinson’s disease).

To help avoid side effects and ensure proper use, talk to your healthcare professional before you take NAT-ONDANSETRON. Talk about any health conditions or problems you may have, including if you:

• have had an allergic reaction to medicines that are similar to NAT-ONDANSETRON such as medicines containing granisetron or palonosetron.
• are pregnant or planning to become pregnant. NAT-ONDANSETRON is not recommended for use during pregnancy.
• are breast feeding or planning to breastfeed. NAT-ONDANSETRON can pass into your breast milk and affect your baby.
• have liver problems.
• have signs of intestinal obstruction or blockage.

• have or have had heart or blood vessel problems, including if you are at a higher risk for these problems. Risk factors include, but are not limited to, if you:

  • have family members who have or have had heart or blood vessel problems,
  • smoke,
  • have high blood pressure,
  • have high cholesterol levels,
  • have diabetes, or
  • are overweight.
• are taking medicines that affect the serotonin in your body (e.g., serotonergic and neuroleptic medications). If you are unsure, ask your healthcare professional.
• have QT/QTc prolongation (a heart rhythm condition) or a family history of QT/QTc prolongation.
• are taking medications that may lead to QT/QTc prolongation or electrolyte imbalances. If you are unsure, ask your healthcare professional.
• have low blood levels of potassium, magnesium, or calcium.

Other warnings you should know about:

Serotonin syndrome: NAT-ONDANSETRON can cause serotonin syndrome, a rare but potentially life-threatening condition. It can cause serious changes in how your brain, muscles and digestive system work. You may develop serotonin syndrome if you take NAT-ONDANSETRON with certain anti-depressants or migraine medications.

Serotonin syndrome symptoms include:

• fever, sweating, shivering, diarrhea, nausea, vomiting;
• muscle shakes, jerks, twitches or stiffness, overactive reflexes, loss of coordination;
• fast heartbeat, changes in blood pressure;
• confusion, agitation, restlessness, hallucinations, mood changes, unconsciousness, and coma.

Myocardial ischemia (lack of blood flow to the heart): Treatment with NAT-ONDANSETRON can cause myocardial ischemia which can lead to a heart attack. This may happen shortly after NAT-ONDANSETRON administration. Some symptoms of myocardial ischemia can include sudden chest pain, pressure or discomfort, feeling faint, feeling anxious, shortness of breath, irregular heartbeat, nausea, and sudden heavy sweating. Your healthcare professional will monitor your health during and after administration of NAT-ONDANSETRON. However, if you notice any symptoms of myocardial ischemia, tell your healthcare professional right away. They may reduce or stop your treatment, and may recommend another therapy.

QT/QTc prolongation: NAT-ONDANSETRON can affect the electrical activity of your heart known as QT/QTc prolongation. This effect can be measured with an electrocardiogram (ECG). In rare cases, QT/QTc prolongation can cause changes to the rhythm of your heart (e.g., fast, slow or irregular heartbeats). This can lead to dizziness, palpitations (sensation of rapid, pounding, or irregular heart beat), fainting, or death. You are at a higher risk if you have a heart disease, are taking certain interacting medicines, are a female, or are over the age of 65 years. It is important to follow the instructions of your healthcare professional with regard to dosing or any special tests. If you experience any symptoms of a possible heart rhythm problem, you should seek immediate medical attention.

Severe allergic reactions: NAT-ONDANSETRON can cause allergic reactions in certain individuals. Symptoms of a severe allergic reaction can include wheezing, sudden chest pain, tightness of the chest, heart throbbing, swelling of eyelids, face or lips, or develop a skin rash, skin lumps or hives. If you notice any signs of a severe allergic reaction, contact your healthcare professional immediately. Do not take any more medicine unless your healthcare professional tells you to do so.

Pregnancy:

• If you are pregnant, there are specific risks for your unborn baby that you must discuss with your healthcare professional.
• If you are able to get pregnant, you may be asked to take a pregnancy test before starting your treatment with NAT-ONDANSETRON.
• You should use effective birth control while you are taking NAT-ONDANSETRON, and for at least 2 days after stopping NAT-ONDANSETRON. Ask your healthcare professional about options of effective birth control.
• If you become pregnant while taking NAT-ONDANSETRON, tell your healthcare professional right away.

Tell your healthcare professional about all the medicines you take, including any drugs, vitamins, minerals, natural supplements or alternative medicines.

The following may interact with NAT-ONDANSETRON:

• medicines called CYP3A4 inducers (e.g., phenytoin, carbamazepine, and rifampicin);
• medicines used to treat heart rhythm disorders (e.g., quinidine, procainamide, disopyramide, amiodarone, sotalol, ibutilide, dronedarone, flecainide, and propafenone);
• medicines used to treat vomiting and nausea called antiemetics (e.g., dolasetron, palonosetron, granisetron, droperidol, chlorpromazine, prochlorperazine, and domperidone);
• medicines called tyrosine kinase inhibitors (e.g., vandetanib, sunitinib, nilotinib, and lapatinib);
• medicines used to manage psychosis or schizophrenia called antipsychotics (e.g., chlorpromazine, pimozide, haloperidol, and ziprasidone);
• medicines used to treat depression called antidepressants (e.g., citalopram, fluoxetine, venlafaxine, tricyclic/tetracyclic antidepressants, amitriptyline, imipramine, and maprotiline);
• medicines used to treat pain called opioids (e.g., methadone and tramadol);
• medicines used to treat bacterial infections called antibiotics (e.g., erythromycin, clarithromycin, telithromycin, tacrolimus, moxifloxacin, levofloxacin, and ciprofloxacin);
• medicines used to treat malaria called antimalarials (e.g., quinine and chloroquine);
• medicines used to treat fungal infections called azole antifungals (e.g., ketoconazole, fluconazole, and voriconazole);
• medicines used to treat cancer (e.g., vorinostat);
• medicines called beta-2 adrenoceptor agonists (e.g., salmeterol and formoterol);
• medicines that can affect electrolyte levels (e.g., diuretics, laxatives, enemas, amphotericin B, and high doses of corticosteroids);
• a medicine used to treat Parkinson’s Disease called apomorphine;
• medicines called serotonergic drugs that can affect the serotonin in the body (e.g., triptans, Selective Serotonin-Reuptake Inhibitors (SSRIs), Serotonin Noradrenalin Reuptake Inhibitors (SNRIs), lithium, sibutramine, fentanyl and its analogues, dextromethorphan, tramadol, tapentadol, meperidine, methadone, pertazocine, St. John’s Wort (Hypericum perforatum), monoamine oxidase inhibitors (MAOIs), linezolid, and methylene blue).

If you are unsure about any medications you are taking, ask your healthcare professional.

How to take NAT-ONDANSETRON:

• The label on the container of your medicine should tell you how often to take your medicine and how many doses you should take each time. If not, or if you are not sure, consult your healthcare professional.
• Do not take more doses, or take them more often than your healthcare professional prescribes. If, however, you vomit within one hour of taking your medicine, you should take the same amount of medicine again. If vomiting persists, consult your healthcare professional.

For NAT-ONDANSETRON tablets:

NAT-ONDANSETRON tablets should be swallowed whole with a liquid.

Usual dose:

Take NAT-ONDANSETRON exactly as your healthcare professional has told you. Your healthcare professional will determine the right dose and length of NAT-ONDANSETRON for you. Your dose will depend on your medical condition, age, current health, and if you take certain other medications. Your healthcare professional may monitor your health throughout your treatment and may interrupt, reduce or stop your dose.

Overdose:

Missed Dose:

If you miss a dose and do not feel sick, take the next dose when it is due.

If you forget to take your medicine and feel sick or vomit, take a dose as soon as possible.

If your healthcare professional decides to stop the treatment, do not keep any leftover medicine unless your healthcare professional tells you to.

What are possible side effects from using NAT-ONDANSETRON?

These are not all the possible side effects you may have when taking NAT-ONDANSETRON. If you experience any side effects not listed here, tell your healthcare professional.

Some side effects may include:

• feeling of flushing or warmth;
• hiccups.

There is no need to stop taking your medicine, but you should tell your healthcare professional about these symptoms at your next visit.

If you feel unwell or have any symptoms that you do not understand, you should contact your healthcare professional immediately.

Serious side effects and what to do about them

Serious side effects and what to do about them

Serious side effects and what to do about them

If you have a troublesome symptom or side effect that is not listed here or becomes bad enough to interfere with your daily activities, tell your healthcare professional.

Reporting Side Effects

Storage:

NAT-ONDANSETRON tablets should be stored between 15°C - 30°C in a dry place.

Keep your medicine in a safe place out of reach and sight of children. Your medicine may harm them.

If you want more information about NAT-ONDANSETRON:

• Talk to your healthcare professional.
• Find the full Product Monograph that is prepared for healthcare professionals and includes this Patient Medication Information by visiting the Health Canada website (https://www.canada.ca/en/health-canada/services/drugs-health-products/drug-products/drug-product-database.html); the manufacturer’s website www.natcopharma.ca, or by calling 1-800-296-9329.

Last Revised April 13, 2022