The most common antihistaminic side effect of cinnarizine is sedation which can vary from slight drowsiness to deep sleep, which includes inability to concentrate, lassitude, dizziness and incoordination. Sedative effects, when they occur, may diminish after a few days.
Cinnarizine may also produce antimuscarinic effects eg, blurred vision, difficulty in micturition, dysuria, dryness of mouth and tightness of chest.
Central effects may include muscular weakness, headache and euphoria.
Weight gain, perspiration or allergic reactions may be observed. Cases of lichen planus and lupus-like symptoms and an isolated case of cholestatic jaundice have been reported.
In elderly people, cases of aggravation or an appearance of extrapyramidal symptoms sometimes associated with depressive feelings have been described during prolonged therapy. The treatment should be discontinued in such cases.
Domperidone has been reported to show allergic reactions eg, rash or urticaria.
Abdominal cramps have been reported. Dystonic reactions (extrapyramidal phenomena) may occur.
Reversible raised serum prolactin levels have been observed which may lead to galactorrhoea and gynaecomastia. Hypertensive crises in patients with phaeochromocytoma may occur with administration of domperidone. Where the blood-brain barrier is not fully developed (mainly in young babies) or is impaired, the possible occurrence of neurological side effects cannot be totally excluded.