Educated patient on new medication Cyproheptadine hydrochloride (CH) is a first-generation antihistamine which is used as an appetite stimulant.Side effects of Cyproheptadine may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:dry mouth, nose, and throat, drowsiness, dizziness, nausea, chest congestion, headache, excitement (especially in children), muscle weakness. Understanding was verbalized.