Brands, Medical Use, Clinical Data
- Phenothiazine Derivatives
- Tablet (2.5 mg)
- Syrup (2.5 mg/5mL)
- Capsule(5 mg)
Brands / Synonyms
(+-)-Alimemazine; (+-)-Trimeprazine; Alimemazine; Alimemazine S,S-dioxide; Alimezine; Bayer 1219; Dosegran; Doxergan; Dysedon; Imakol; Levoprome; Methylpromazine; Oxomemazin; Oxomemazina [INN-Spanish]; Oxomemazine; Oxomemazine [DCF:INN]; Oxomemazinum [INN-Latin]; Oxymemazine; Panectyl; Repeltin; Repetin; Temaril; Teralen; Theralene; Trimeperazine; Trimeprazine 5,5-dioxide; Trimeprazine hemi-(+)tartrate; Trimeprazine Tartrat; Trimeprazine Tartrate; Vallergan
Used to prevent and relieve allergic conditions which cause pruritus (itching) and urticaria (some allergic skin reactions).
Trimeprazine (also known as Alimemazine) is a tricyclic antihistamine, similar in structure to the phenothiazine antipsychotics, but differing in the ring-substitution and chain characteristics. Trimeprazine is in the same class of drugs as chlorpromazine (Thorazine) and trifluoperazine (Stelazine); however, unlike the other drugs in this class, trimeprazine is not used clinically as an anti-psychotic. It acts as an anti-histamine, a sedative, and an anti-emetic (anti-nausea). Trimeprazine is used principally as an anti-emetic, to prevent motion sickness or as an anti-histamine in combination with other medications in cough and cold preparations. Tricyclic antihistamines are also structurally-related to the tricyclic antidepressants, explaining the antihistaminergic adverse effects of these two drug classes and also the poor tolerability profile of tricyclic H1-antihistamines.
Mechanism of Action
Trimeprazine competes with free histamine for binding at HA-receptor sites. This antagonizes the effects of histamine on HA-receptors, leading to a reduction of the negative symptoms brought on by histamine HA-receptor binding.
Well absorbed in the digestive tract.
Symptoms of overdose clumsiness or unsteadiness, seizures, severe drowsiness, flushing or redness of face, hallucinations, muscle spasms (especially of neck and back), restlessness, shortness of breath, shuffling walk, tic-like (jerky) movements of head and face, trembling and shaking of hands, and insomnia.
Biotrnasformation / Drug Metabolism
Contraindicated in hypersensitivity to H1-receptor antagonists, acute asthma attack, and lower respiratory tract disease.
Barbiturates, narcotics, hyptonics, tricyclic antidepressants, and alcohol can increase CNS depression when administered concomitantly with trimeprazine. Trimeprazine also decreases the effect of heparin and oral anticoagulants, while MAOIs can increase the effect of trimeprazine.