Brazil. The Secretária de Vigilância Sanitária has issued a warning concerning the possibility of arrhythmias occurring in patients taking astemizole, especially at dosages higher than the recommended maximum. The product information has been revised to include this warning. These reactions have been observed when other medicines, such as antihypertensives (mibefradil) and antibiotics (clarithromycin and troleandomycin), have been used concomitantly with astemizole.
Adverse reactions have also been associated with the concomitant use of astemizole with other medicines, such as HIV protease inhibitors (indinavir, ritonavir, saquinavir and nelfinavir), serotonin inhibitors (fluoxetine, fluvoxamine, sertraline, nefazodone and paroxetine), and the antiasthmatic zileuton. Grapefruit juice also interferes with the metabolism of astemizole.
Patients with hepatic disease should not take astemizole.
[See also Pharmaceuticals Newsletter Nos. 1&2, 3&4, 7&8, 1998 and 9&10, 1997]
Reference: Alerta Sanitário! No. 1/98, Secretária de Vigilância Sanitária, Ministry of Health, Brasilia.