Medicines & Supplements A to Z > Flagyl


Last updated on 19/10/2021.

Overview   |   Dosage   |    Side Effects   |   Precautions  |   Tips  |   Where To Buy  

GENERIC NAME: Metronidazole


DRUG CLASS: Antibiotics, Antiprotozoals

SUB CLASS: Nitroimidazole

USED FOR: Anaerobic infections, Bacterial vaginosis, Amoebiasis

– 200mg (tablets)
– 200mg/5ml (oral suspension)

What is Flagyl for?

Flagyl is a brand product that contains Metronidazole, which acts as an antibiotic and antiprotozoal agent. Its broad range of actions is used to treat many types of infections, including bacterial and protozoal.

How to use it?

Flagyl is available as tablets or oral suspension. The usual adult dose is 400-500 mg three times a day. The dose may vary depending on your type of infection.

What are the side effects of Flagyl?

Common side effects of Flagyl include nausea and vomiting, metallic taste and headache.

Who should not take Flagyl?

– People who are allergic to metronidazole, nitroimidazole derivatives, or any component of the formulation
Pregnant women (first trimester) with trichomoniasis

Pharmacist Tips:

Do not drink alcohol while taking this drug and for at least 72 hours after your last dose, as it can cause severe symptoms like abdominal cramps, nausea, vomiting, and flushing.
– Avoid exposure to sunlight as Flagyl can cause light sensitivity.

Common dosing schedule:
Flagyl should be taken with food to reduce stomach upset. It is usually taken every 8 hours (3 times per day).

This schedule is for reference only, adjustments may be made according to individual needs.

Some common medications Flagyl may interact with:
– Alcohol
– Anticoagulants, e.g. Warfarin
– Disulfiram

Please notify your doctor or pharmacist if you are taking the above medication, dosage adjustments might be needed.

Where to buy Flagyl in Hong Kong?

In Hong Kong, Flagyl is a prescription only medicine, and requires a prescription from a doctor to be purchased in a pharmacy. It can also be obtained from doctors. To find a pharmacy near you, refer to the list of pharmacies (“Authorized Sellers of Poisons”) from the Hong Kong Department of Health.

For more information about drug names and ingredients, you can visit Hong Kong’s Drug Office at

Need more information?

For detailed information about the use of Flagyl in children, pregnancy and breastfeeding, and for questions about drug interactions, please check with your pharmacist or doctor.

Disclaimer: our goal is to provide you with the most relevant drug information and common dosage for Hong Kong. This information does not constitute medical advice. For specific treatment recommendations and advice, always discuss with your doctor or pharmacist, and follow the instructions included with your specific medicine.