Astemizole
Astemizole (marketed under the brand name Hismanal, developmental code R43512) was a second-generation antihistamine drug that has a long duration of action. Astemizole was discovered by Janssen Pharmaceutica in 1977. It has been withdrawn from the market in most countries because of rare but potentially fatal side effects (QTc interval prolongation and related arrhythmias due to hERG channel blockade).
Bamipine
Side effects are typical of an old (first-generation) antihistamine: tiredness in adults, agitation in children, mydriasis (dilation of the pupils). These effects are rare when bamipine is applied topically as an ointment. Allergic and hypersensitivity reactions are also rare. Acute eczema can be worsened by bamipine ointment.