Patient Medication Information: uses, side effects, how to take - Apo-Metronidazole Tablets
Serious warnings and precautions box
- Cases of severe skin reactions (Severe Cutaneous Adverse Reactions (SCAR)) have been reported with metronidazole. Stop using APO-METRONIDAZOLE TABLETS at the first sign of rash, sores or other skin reactions. For more information read the “Serious side effects and what to do about them” table, below.
What APO-METRONIDAZOLE TABLETS is used for:
APO-METRONIDAZOLE TABLETS is used to treat adults with:
- infections of the genital tract (such as trichomoniasis: a sexually transmitted infection, bacterial vaginosis: bacterial infection of the vagina).
- infections of the brain or lung.
It is also used treat adults and children with:
- Amebiasis (a parasitic infections of the liver or intestine).
- Giardiasis (a parasitic infection in the intestines).
Antibacterial and antiprotozoal drugs like APO-METRONIDAZOLE TABLETS treat only bacterial and protozoal infections. They do not treat viral infections such as the common cold. Although you may feel better early in treatment, APO-METRONIDAZOLE TABLETS should be used exactly as directed. Misuse or overuse of APO-METRONIDAZOLE TABLETS could lead to the growth of bacteria/protozoans that will not be killed by APO-METRONIDAZOLE TABLETS (bacterial/protozoan resistance). This means that APO-METRONIDAZOLE TABLETS may not work for you in the future. Do not share your medicine with anyone.
How APO-METRONIDAZOLE TABLETS works:
APO-METRONIDAZOLE TABLETS belong to a group of medicines called antibacterial - antiprotozoal.
APO-METRONIDAZOLE TABLETS works by killing bacteria and parasites (protozoans) that cause infections in your body.
The ingredients in APO-METRONIDAZOLE TABLETS are:
Medicinal ingredient: metronidazole
Non-medicinal ingredients: colloidal silicon dioxide, croscarmellose sodium, magnesium stearate and microcrystalline cellulose.
APO-METRONIDAZOLE TABLETS comes in the following dosage forms:
Tablets: 250 mg
Do not use APO-METRONIDAZOLE TABLETS if:
- you are allergic (hypersensitive) to metronidazole, nitroimidazoles (e.g. tinidazole) or any of the ingredients in APO-METRONIDAZOLE TABLETS or components of the container (see What are the ingredients in APO-METRONIDAZOLE TABLETS).
- you have a genetic disorder called Cockayne Syndrome. Severe liver damage that may be fatal has happened when people with Cockayne syndrome have taken metronidazole.
- you have a disease of the nervous system.
- you have a history of blood disorders.
- you have hypothyroidism (underactive thyroid gland) or hypoadrenalism (underactive adrenal glands).
To help avoid side effects and ensure proper use, talk to your healthcare professional before you take APO-METRONIDAZOLE TABLETS. Talk about any health conditions or problems you may have, including if you:
are pregnant, think you are pregnant, or plan to get pregnant.
- are breastfeeding, or planning to breastfeed, as metronidazole is excreted in human breast milk.
- have other infections.
- have liver problems.
- have kidney problems.
- are sexually active.
- are taking APO-METRONIDAZOLE TABLETS for the first time or have any nervous system problems.
- have any blood disorder (e.g. leukemia, hemophilia, or other).
Other warnings you should know about:
Driving and Operating Machinery:
- APO-METRONIDAZOLE TABLETS may make you experience confusion, dizziness, vertigo (spinning sensation), hallucinations, convulsions (seizures) or problems with your eyesight (blurred vision). Do not drive or operate heavy machinery while taking APO-METRONIDAZOLE TABLETS.
Medical Tests
- Your healthcare professional may order medical tests based on your medical history and how long you have been taking APO-METRONIDAZOLE TABLETS.
- APO-METRONIDAZOLE TABLETS may affect the results of certain medical tests. Tell your healthcare professional if you are taking APO-METRONIDAZOLE TABLETS and you need a medical test for another health condition.
Reproductive Health
- If a sexual partner shows signs of infection, the partner should be examined and treated by the doctor as well.
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 APO-METRONIDAZOLE TABLETS:
- Amiodarone – used to treat certain heart rhythm conditions.
- Busulfan, a medicine used to treat certain blood cancer.
- Carbamazepine – used to treat epilepsy and nerve pain.
- Cyclosporin, a medicine used to prevent organ rejection after a transplant.
Disulfiram, a medicine used to treat alcoholism.
- Lithium, a medicine used as a psychiatric medication.
- Phenytoin, a medicine used to treat seizures.
- Phenobarbital, a medicine used to treat insomnia, anxiety or tension or to control seizures.
- Quinidine – used to treat malaria and certain heart rhythm conditions.
- Tacrolimus – used to help with organ transplants.
- Vecuronium, an agent used to relax muscles during surgical procedures.
- Warfarin, a blood thinner used treat heart conditions.
- 5-fluorouracil, a medicine used to treat cancer.
- Medications that may cause heart rhythm changes (QT prolongation), like certain antiarrhythmics (medicines for heart rhythm disorders), certain antibiotics, and psychotropic medicines.
Do not drink alcohol while taking APO-METRONIDAZOLE TABLETS and for at least 1 day after your last dose. Drinking alcohol while using APO-METRONIDAZOLE TABLETS might cause side effects, such as feeling sick (nausea), being sick (vomiting), stomach pain, hot flushes, very fast or uneven heartbeat (palpitations) and headache.
How to take APO-METRONIDAZOLE TABLETS:
- You should not be left unattended for 2 hours after your first use of APO-METRONIDAZOLE TABLETS.
- Although you may feel better early in treatment, APO-METRONIDAZOLE TABLETS should be used exactly as directed.
- Misuse or overuse of APO-METRONIDAZOLE TABLETS could lead to the growth of bacteria that will not be killed by APO-METRONIDAZOLE TABLETS (resistance). This means that APO-METRONIDAZOLE TABLETS may not work for you in the future.
- Do not share your medicine.
Usual dose:
Your healthcare professional will decide how much APO-METRONIDAZOLE TABLETS you should take depending on the type of infection you have and your medical history.
Adults:
The usual dose is 250 mg to 500 mg every 8 to 12 hours for 5 to 10 days.
Children (under 18 years old):
The usual dose is 25 to 50 mg/kg/day divided into 2 to 3 doses each day for 5 to 7 days.
Overdose:
If you think you, or a person you are caring for, have taken too much APO-METRONIDAZOLE TABLETS, contact a healthcare professional, hospital emergency department, regional poison control centre or Health Canada’s toll-free number, 1-844 POISON-X (1-844-764-7669) immediately, even if there are no signs or symptoms.
Missed dose:
If you forget to take APO-METRONIDAZOLE TABLETS, take them as soon as you remember. However, if it is almost time for your next dose, skip the missed dose. Do not use a double dose to make up for a forgotten dose.
Possible side effects from using APO-METRONIDAZOLE TABLETS:
These are not all the possible side effects you may have when taking APO-METRONIDAZOLE TABLETS. If you experience any side effects not listed here, tell your healthcare professional.
Like all medicines, APO-METRONIDAZOLE TABLETS can cause side effects, although not everybody gets them.
These side effects may include:
- Constipation
- Unpleasant taste in the mouth
- Dry mouth
- Furred tongue or tongue discoloration
- Chest pain
- Feeling sick (nausea), being sick (vomiting)
- Upset stomach
- Stomach pain
- Noise such as buzzing, ringing, or whistling heard in the ear
- Loss of appetite
- Feeling sleepy or dizzy
- Unpleasant metallic taste
- Dark urine
- Painful urination
- Flushing
- Headache
- Trouble sleeping
- Itching, hives, rash
Serious side effects and what to do about them
| Frequency/Side Effect/Symptom | Talk to your healthcare professional | Stop taking this drug and get immediate medical help | |
|---|---|---|---|
| Frequency/Side Effect/Symptom | Talk to your healthcare professional | Stop taking this drug and get immediate medical help | |
| Frequency/Side Effect/Symptom | Talk to your healthcare professional | Stop taking this drug and get immediate medical help | |
| Frequency/Side Effect/Symptom | Talk to your healthcare professional | Stop taking this drug and get immediate medical help | |
| Only if severe | In all cases | ||
| Only if severe | In all cases | ||
| Only if severe | In all cases | ||
| Only if severe | In all cases | ||
| Allergic reaction: swelling of the face, mouth, tongue or throat, hands, difficulty in breathing or swallowing, wheezing; drop in blood pressure, feeling sick to your stomach and throwing up itching, rash, red spots and blisters | √ | ||
Severe Cutaneous Adverse Reactions (severe skin reactions that may also affect other organs):
or face.
body aches, swollen glands, cough.
or discomfort.
| √ | ||
| Pseudomembranous colitis (bowel inflammation): severe or persistent diarrhea, abdominal pain, nausea and vomiting, fever | √ | ||
| Drug reaction with eosinophilia and systemic symptoms (DRESS) (serious skin reaction that may affect more than one or more organs): fever, severe rash, peeling skin, swollen lymph glands, flu-like feeling, yellow skin or eyes, shortness of breath, dry cough, chest pain or discomfort, feel thirsty, urinating less often, less urine | √ | ||
| Hearing loss | √ | ||
Heart Problems: very fast or uneven heartbeat, chest pain, dizziness, weakness, blurred vision, fainting. This may also happen when APO-METRONIDAZOLE TABLETS is taken with drugs that can cause QT prolongation (a heart rhythm condition). | √ | ||
| Leukopenia / Neutropenia (decreased white blood cells): infections, fatigue, fever, aches, pains and flu-like symptoms | √ | ||
| Liver problems: including cases of liver failure with symptoms such as intense fatigue, yellowing of the skin and eyes (jaundice), right upper stomach area pain or swelling, nausea or vomiting, unusual dark urine, abdominal pain, unusual tiredness. | √ | ||
| Meningitis (inflammation of the thin tissue that surrounds the brain and spinal cord): fever, nausea, vomiting, headache, stiff neck, extreme sensitivity to bright light, confusion, seizures, sleepiness or difficulty waking, no appetite or thirst | √ | ||
| Mental health problems: irrational thoughts, feeling confused or feeling depressed and seeing hearing things that are not there (hallucinations), thoughts or actions of self-harm or suicide | √ | ||
| Muscular Disorders: muscle spasms, muscle aches and pain, joint stiffness | √ | ||
| Nervous system problems: inability to coordinate voluntary movements, problems using your arms and legs, problems with speaking or feeling confused, convulsions, tingling sensation on the skin, stiff neck associated with headache, extreme sensitivity to bright light, have spinning sensations (vertigo). | √ | ||
| Posterior Reversible Encephalopathy Syndrome (brain swelling): Headache, confusion, visual disturbances, seizures | √ | ||
| Eye sight problems: pain when moving the eye, blurred vision, double vision, vision loss | √ | ||
| Pancreatitis (inflammation of the pancreas): severe abdominal pain which may reach through to your back, especially associated with nausea, vomiting and fatigue. | √ | ||
| Peripheral neuropathy: Numbness, tingling, pain, or a feeling of weakness, in the arms or legs, sensitivity to touch | √ | ||
| Seizures (fit): uncontrollable shaking with or without loss of consciousness | √ | ||
| Stevens-Johnson syndrome (SJS) (severe skin rash): redness, blistering and/or peeling of the skin and/or inside of the lips, eyes, mouth, nasal passages or genitals, accompanied by fever, chills, headache, cough, body aches or swollen glands. | √ | ||
| Thrombophlebitis (blood clot in the vein of the leg or arm): swelling and redness along the vein which is extremely tender or painful when you touch the area | √ | ||
| Thrombocytopenia (low blood platelets): bruising or bleeding for longer than usual if you hurt yourself, fatigue and weakness | √ | ||
| Toxic Epidermal Necrolysis (TEN) (severe skin reaction): redness, blistering and/or peeling of large areas of the body | √ | ||
| Vaginal Yeast Infection: vaginal dryness, burning and discharge | √ | ||
Gastrointestinal problems: Abdominal pain, cramps, diarrhea with possible bloody stools | √ | ||
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
You can report any suspected side effects associated with the use of health products to Health Canada by:
- Visiting the Web page on Adverse Reaction Reporting (canada.ca/drug-device-reporting) for information on how to report online, by mail or by fax; or
- Calling toll-free at 1-866-234-2345.
NOTE: Contact your healthcare professional if you need information about how to manage your side effects. The Canada Vigilance Program does not provide medical advice.
Storage:
Store at room temperature (15°C to 30°C). Protect from light.
Keep out of reach and sight of children.
If you want more information about APO-METRONIDAZOLE TABLETS:
- 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 Drug Product Database website (Drug Product Database: Access the database); the manufacturer’s website (http://www.apotex.ca/products), or by calling 1-800-667-4708.
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Date of Authorization: 2026-04-20