Last reviewed 2026-04-20 · How we verify

Lariam (MEFLOQUINE HYDROCHLORIDE)

Lariam (Mefloquine Hydrochloride) is a small molecule antimalarial drug originally developed by the US Army and currently owned by Roche. It targets the adenosine receptor A2a and is FDA-approved for treating and preventing chloroquine-resistant Plasmodium falciparum malaria, as well as vivax malaria. Lariam is available as a generic medication due to its off-patent status. Key safety considerations include potential neuropsychiatric side effects. It has a bioavailability of 80%.

At a glance

Approved indications

• Chloroquine Resistant Plasmodium Falciparum Malaria
• Chloroquine-Resistant Plasmodium Falciparum Malaria Prevention
• Vivax malaria

Boxed warnings

• WARNING Mefloquine may cause neuropsychiatric adverse reactions that can persist after mefloquine has been discontinued. Mefloquine should not be prescribed for prophylaxis in patients with major psychiatric disorders. During prophylactic use, if psychiatric or neurologic symptoms occur, the drug should be discontinued and an alternative medication should be substituted (see WARNINGS ).

Common side effects

• Vomiting
• Nausea
• Diarrhea
• Abdominal pain
• Dizziness
• Headache
• Fever
• Chills
• Fatigue
• Loss of appetite
• Tinnitus
• Loss of balance

Drug interactions

• P-glycoprotein Substrates
• halofantrine
• rifampicin
• ziprasidone

Key clinical trials

• A Trial to Compare the Efficacy, Safety and Tolerability of Combinations of 3 Anti-malarial Drugs Against Combina-tions of 2 Anti-malarial Drugs. (PHASE3)
• Temozolomide, Memantine Hydrochloride, Mefloquine, and Metformin Hydrochloride in Treating Patients With Glioblastoma Multiforme After Radiation Therapy (PHASE1)
• A Trial to Compare the Efficacy, Safety and Tolerability of Combinations of 3 Anti-malarial Drugs Against Combinations of 2 Anti-malarial Drugs (Asia) (PHASE3)
• Efficacy of Mefloquine as Prophylaxis Against COVID-19: A Placebo-control, Randomized Clinical Trial (PHASE2,PHASE3)
• A Study by the Tracking Resistance to Artemisinin Collaboration (TRAC) (PHASE2,PHASE3)
• Safe and Efficacious Artemisinin-based Combination Treatments for African Pregnant Women With Malaria (PHASE3)
• Evaluation of Potential Effect of Artemether - Lumefantrine and Malaria Drugs on Auditory Function (PHASE4)
• Effectiveness of Artemisinin Combination Regimens in Falciparum Malaria (PHASE4)

Primary sources

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