Mood disorder after malaria prophylaxis with mefloquine (two case reports)

Introduction

Mefloquine (Lariam) is the drug of choice as malaria prophylaxis for travel to chloroquine-resistant areas. Severe neuropsychiatric side effects are rare. We report two clinical cases of mood disorders: mania and a major depressive episode with psychotic characteristics in two patients with mefloquine antimalarial prophylaxis.

First clinical case

A 31-year-old man had taken mefloquine at a rate of 250 mg/week as malaria prophylaxis for his mission in Democratic Republic of Congo. He developed mania with psychotic symptoms after taking five tablets of 250 mg of mefloquine. He exhibited an elevated mood and also developed delusions of grandeur, reference and persecution, with auditory hallucinations. The physical examination and the blood laboratory tests were normal. The patient was treated with an atypical neuroleptic (olanzapine 20 mg/d) leading to a complete resolution of symptomatology at the end of 3 weeks.

Second clinical case

A 27-year-old man presented a major depressive episode with psychotic symptoms after 1 week on his return from a stay in Democratic Republic of Congo, where he had taken mefloquine during 6 months as malaria prophylaxis (250 mg/week). His physical examination and investigations (full blood test, serology and MRN) were normal. The patient was treated with clomipramine (150 mg/d) and olanzapine (20 mg/d). The outcome was favorable after 4 weeks.

Discussion

Mefloquine is widely accepted as a safe and effective treatment and a prophylactic agent for chlorquine-resistant malaria. Common neuropsychiatric adverse effects of mefloquine can occur in up to 40% of patients, such as dizziness, sleep disturbances, anorexia, ataxia, and fatigue. Other more serious adverse reactions are rare. They are represented primarily by panic attacks, convulsions, acute psychosis, paranoid delusions, suicidal ideation, disorders of mood: major depressive episode and the manic excitation. The incidence of such neuropsychiatric effects is 1/10,000 to 1/15,000 during the prophylactic treatment. The causal mechanism for the side effects is not known. Several risk factors increasing the neurotoxicity of mefloquine can be identified, the patient with personal or family history of psychiatric disorders are more frequently concerned. Alcohol and the association with other drugs (like quinine) are two other risk factors.

Conclusion

It is relevant for medical practitioners to be aware of the severe neuropsychiatric side effects of mefloquine as malaria prophylaxis. It requires investigation of the risk factors such as personal or family history of psychiatric disorders.