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Antimalarial (quinoline-methanol)

Mefloquine: uses, side effects & precautions

Also known as Lariam.

Ces informations sont fournies à titre indicatif uniquement et ne constituent pas un avis médical. Consultez toujours un professionnel de santé qualifié pour toute préoccupation médicale personnelle. En cas d'urgence, appelez votre numéro d'urgence local.

What it is used for

  • Prevention of malaria for travellers to certain regions
  • Treatment of malaria caused by sensitive parasite strains

How it works

Mefloquine kills malaria parasites in the blood by interfering with their ability to survive inside red blood cells.

How it is taken

Taken as oral tablets, usually with food and plenty of water. For prevention it is taken once weekly, started before travel and continued for a period afterward; for treatment a short course is used. Take it exactly as your doctor or pharmacist directs.

No doses here on purpose. The right strength and schedule depend on you — only a doctor or pharmacist should set them. Always follow your prescription and the label.

Common side effects

  • Nausea
  • Dizziness
  • Headache
  • Diarrhea
  • Vivid or disturbing dreams
  • Difficulty sleeping

Serious effects — get help

  • New or worsening anxiety, depression, paranoia, hallucinations, or thoughts of harming yourself — stop and seek urgent care
  • Seizures — seek emergency care
  • Irregular heartbeat or fainting — seek urgent care
  • Severe dizziness, balance problems, or ringing in the ears that may persist — contact your clinician

If a reaction is severe — for example trouble breathing, swelling of the face or throat, or collapse — go to the nearest emergency room now or call your local emergency number. Do not wait for an online consultation.

Interactions to watch

  • Other medicines that affect heart rhythm
  • Some antiepileptic medicines (effect may be reduced)
  • Other antimalarials such as quinine or chloroquine
  • Medicines affecting mood or the nervous system

Who should take care

  • Tell your clinician about any history of depression, anxiety, psychiatric illness, or seizures, as it may not be suitable
  • Report heart-rhythm or liver conditions
  • Because of possible neurological and psychiatric effects, you may be advised to start it before travel to check tolerance
  • Inform your clinician if pregnant or breastfeeding
  • Avoid in activities needing fine balance if you feel affected

Frequently asked questions

Why might I be told to start it weeks before travel?
Starting earlier lets you and your clinician check how you tolerate it before you are away, since some people get mood or sleep effects. Follow the schedule you are given.
What mental-health changes should I watch for?
Watch for new anxiety, low mood, unusual fear, confusion, or any thoughts of self-harm. If these appear, stop and seek urgent medical help.
Is it a once-a-week tablet?
For prevention it is usually taken once weekly on the same day. Take it exactly as your clinician or the label directs.
Can anyone use it for malaria prevention?
It is not suitable for everyone, especially people with certain mental-health or seizure histories. Your clinician will assess whether it fits you.
Is Mefloquine safe to take?
For most people it is safe when taken exactly as a doctor or pharmacist advises and as printed on the label. Tell your clinician about your other medicines and health conditions, and seek urgent care for any serious reaction.

Related conditions

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