indication

Mepyramine is a first generation antihistamine used in treating allergies, ymptomatic relief of hypersensitivity reaction, and in pruritic skin disorders.

mechanism of action

Mepyramine is a histamine H1 receptor inverse agonist. It binds to a G protein-coupled form of the receptor and promotes a G protein-coupled inactive state of the H1 receptor that interferes with the Gq/11-mediated signaling. Mepyramine competes with histamine for binding at H₁-receptor sites on the effector cell surface, resulting in suppression of histaminic edema, flare, and pruritus. The sedative properties of Mepyramine occur at the subcortical level of the CNS.

toxicity

The signs and symptoms that are produced after the acute overdosage of Mepyramine include Convulsions, Coma, Ataxia, Hyperpyrexia, Tremor, Extrapyramidal effects, Excitement.