The question concerns a 55-year-old male with dizziness. In 1982 he was treated with chloroquine as

Fråga: The question concerns a 55-year-old male with dizziness. In 1982 he was treated with chloroquine as malaria prophylaxis when travelling abroad for two weeks. The patient claims that the dizziness started after the chloroquine treatment. The patient has not received any further chloroquine treatment. Examination by an ear-nose-throat specialist has shown that the patient suffers an impaired sense of balance. Could chloroquine in a prophylactic treatment dosage give irreversible side-effect symptoms such as dizziness, vertigo or an impaired sense of balance?

Sammanfattning: No documentation has been found in the literature concerning irreversible side-effects as a result of chloroquine treatment, such as dizziness, vertigo or an impaired sense of balance. The reported symptoms and impairment is not likely to have been caused by the chloroquine treatment.

Svar: Neither communication with a physician experienced in the subject, Yakoub Aden Abdi, at the Department of Clinical Pharmacology, Huddinge Hospital (1), nor an extensive literature search including Medline, has revealed any reports of irreversible dizziness, vertigo or an impaired sense of balance (2). Minor side-effects such as nausea, vomiting, diarrhoea, itching and dizziness may occur with dosages used for prophylactic treatment of malaria. With cumulative doses of chloroquine of more than 100 gram base, the risk of irreversible retinopathy is substantial. During long-term treatment side-effects such as diplopia, blurred vision, accommodation problems, apathy, anxiety, headache, dizziness and vertigo, are common. These side-effects are probably concentration dependent and will subside after stopping treatment. 1 Communication with Dr Yakoub Aden Abdi, Department of Clinical Pharmacology, Huddinge Hospital 2 Gustafsson LL, Beerman B, Abdi YA: Handbook of drugs for tropical parasitic infections. Taylor & Francis, London, 1987