NEUROPSYCHIATRIC EFFECTS OF ANTIMALARIALS

Objective: To study the neuro-psychiatric adverse effects of antimalar ial drugs. Setting: Persons who visited a Travel Clinic in Rotterdam o ver a period of 3 months. Design: Prospective cohort study on 394 pers ons taking mefloquine, 493 persons taking proguanil and 340 persons no t taking antimalarial drugs who visited Africa, South America, Asia, o r the Middle East. Methods: All persons received a structured question naire within 14 days of their return to the Netherlands. The questionn aire consisted of questions regarding use of alcohol. smoking, general health, medical history, tropical diseases during the trip, and other medicines, and contained an extensive list of general complaints rega rding all body systems at four levels of severity. A modified and vali dated version of the Profile of Mood States was included. Results: In the study period, 2541 persons visited the Travel Clinic, of whom 1791 (70%) were both eligible and willing to co-operate. Of these 1791, da ta were obtained from 1501 (84%). Insomnia was most frequently encount ered in users of mefloquine and mouth ulcers in proguanil users. After adjustment for gender, age, destination, and alcohol use, the relativ e risk for insomnia to mefloquine versus non-users of antimalarials wa s 1.6, and the excess risk was 6 per 100 users over an average period of 2 months. There were no significant differences between groups in d epression, anxiety, agitation, and confusion. Stratification by gender demonstrated that insomnia was more common in women on mefloquine, bu t not in men. Also, women more frequently mentioned palpitations as an adverse event. After adjustment for age, destination, and alcohol use in women, the relative risks for insomnia and palpitations to mefloqu ine versus non-use of antimalarials were 2.4, and 22.5, respectively. When travellers were specifically asked for the adverse reactions they had experienced, anxiety, vertigo, agitation, and nightmares were sig nificantly more frequently mentioned by mefloquine users. Conclusion: Insomnia was more commonly encountered during use of mefloquine than p roguanil or during nonuse of antimalarials.