Saravana Kumar Ramasubbu, Ann George, S K Hasib Reja
Mefloquine is an effective antimalarial drug widely used for malaria treatment and chemoprophylaxis. However, its use has been associated with a range of neuropsychiatric adverse effects, ranging from mild sleep disturbances to severe psychiatric reactions. The aim of this study is to systematically review the available evidence on neuropsychiatric adverse effects associated with mefloquine use and to characterize their clinical spectrum, time to onset, and reported outcomes. A systematic literature search was conducted to identify studies reporting neuropsychiatric adverse effects associated with mefloquine. Studies meeting the predefined eligibility criteria were included, and relevant clinical and adverse effect data were extracted. The methodological quality of included studies was assessed using the National Institutes of Health (NIH) Study Quality Assessment Tools. Of 207 records identified, 25 studies were included after removing duplicates and applying the eligibility criteria. These comprised 17 case reports and 8 clinical studies. The case reports described 19 patients aged 7-63 years with a wide range of neuropsychiatric manifestations. Frequently reported adverse effects included hallucinations, depression, anxiety, and insomnia, while psychosis, confusion, and mania were also reported. Other manifestations included paranoia, delusions, restlessness, nightmares, depersonalization/derealization, suicidal ideation, and delirium. The time to onset ranged from a few hours to several months after exposure. Clinical studies demonstrated variable frequencies of neuropsychiatric adverse effects across different populations and study designs. Mefloquine is associated with a broad spectrum of neuropsychiatric adverse effects, ranging from mild symptoms such as anxiety and insomnia to severe psychiatric manifestations. Early recognition and careful patient selection are important when prescribing mefloquine.