Indication: symptomatic relief of allergy such as hay fever, urticaria, emergency treatment of anaphylactic reactions; premedication in anesthesia; sedation; motion sickness.

Cautions: intramuscular injection may be painful.

Contra-indications: porphyria.

Side Effects: Headache, psychomotor impairment, and antimuscarinic effects such as urinary retention, dry mouth, blurred vision, and gastro-intestinal disturbances. Cardiovascular adverse effects more commonly seen after injection: bradycardia, tachycardia, transient minor increases in blood pressure and occasional hypertension. Jaundice and blood dyscrasias have been reported, and extrapyramidal effects may occur at high doses. Venous thrombosis has been reported at the site of intravenous injections, and arteriospasm and gangrene may follow inadvertent intra-arterial injection. intramuscular injection may be painful.

Dose: by mouth, 25mg at night, may be increased to 50- 75mg at night if necessary.

Child below 2 years, not recommended. 2-5 years, 5-15mg daily.

5-10 years, 10-25mg daily.

By IM injection, adult, 25-50mg.

Child 5-10 years, half oral dose i.e 6.25-12.5mg. By slow IV injection after dilution with water for injection to 2.5mg/ml, 25-50mg.

Max. parenteral dose, 100mg.