Mefloquine: uses, side effects & brands

Written & medically reviewed by Dr. Sanjay Anbu, MBBS · Last reviewed 5 November 2026

Mefloquine treats and prevents malaria; it can cause vivid dreams or mood effects. It belongs to the Antimalarial (treatment) group. These treat malaria; the choice depends on the malaria type and region.

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Drug type — dosing is set by your doctor

Measure	Range
Drug class	Antimalarial (treatment)
Type	Prescription
Dose	Individual — ask your doctor or pharmacist

What it is used for

Prevents malaria in travellers to some high-risk areas
Treats some cases of uncomplicated malaria
Useful where certain other antimalarials do not work

Common brand names

India: Mefax, Larimef
Worldwide: Lariam

Common side effects

Vivid dreams or trouble sleeping
Dizziness or loss of balance
Nausea or diarrhoea
Anxiety or low mood

Before taking it — precautions

Not for people with a history of depression, anxiety, psychosis or seizures
Tell your doctor about heart rhythm problems and other heart or epilepsy medicines
Take care with tasks needing balance, such as driving, diving or flying

When to see a doctor urgently

Anxiety, depression, confusion, hallucinations or suicidal thoughts (urgent)
Fits (urgent)
Severe dizziness, ringing in the ears or loss of balance

Not a prescription — no dose shown. The right dose of mefloquine depends on age, weight, kidney/liver function and the condition, so MedDroid does not show a dose here. Always get your dose from a doctor or pharmacist and the leaflet inside the pack. General educational information only.

Frequently asked questions

Can mefloquine affect mood?

Yes. It can cause anxiety, low mood, nightmares or rarely more serious mental effects; stop and seek help if these happen.

Why start it before travelling?

Starting early helps build up the medicine and shows whether you tolerate it before you leave.

Can effects last after stopping?

Rarely, dizziness or balance problems can persist; tell your doctor about any symptoms.

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Sources & further reading

Reviewed by Dr. Sanjay Anbu, MBBS. MedDroid is an AI medical assistant and can make mistakes. It provides general health information, not a diagnosis or medical advice — always consult a qualified clinician. In an emergency, contact your local emergency number immediately.