- Metabolism: Unknown, but most likely hepatic as with other phenothiazines.
- Uses/Sources: Propiomazine is largely used for its antihistamininc sleep inducing effects in treating insomnia.
- Health Effects: They cause slurred speech, disorientation and "drunken" behavior. They are physically and psychologically addictive.
- Symptoms: Rare, serious side effects include convulsions (seizures); difficult or unusually fast breathing; fast or irregular heartbeat or pulse; fever (high); high or low blood pressure; loss of bladder control; muscle stiffness (severe); unusual increase in sweating; unusually pale skin; and unusual tiredness or weakness.
Mechanism of Action
|Target Name||Mechanism of Action||References|
Muscarinic acetylcholine receptor M1
Muscarinic acetylcholine receptor M2
Muscarinic acetylcholine receptor M3
Muscarinic acetylcholine receptor M4
Muscarinic acetylcholine receptor M5
5-hydroxytryptamine receptor 2A
5-hydroxytryptamine receptor 2C
Alpha-1A adrenergic receptor
D(2) dopamine receptor
D(4) dopamine receptor
D(1A) dopamine receptor
Histamine H1 receptor
Alpha-1B adrenergic receptor
Alpha-1D adrenergic receptor
|Propiomazine is an antagonist at types 1, 2, and 4 dopamine receptors, serotonin (5-HT) receptor types 2A and 2C, muscarinic receptors 1 through 5, alpha(1)-receptors, and histamine H1-receptors. Propiomazine's antipsychotic effect is due to antagonism at dopamine and serotonin type 2 receptors, with greater activity at serotonin 5-HT2 receptors than at dopamine type-2 receptors. This may explain the lack of extrapyramidal effects. Propiomazine does not appear to block dopamine within the tubero-infundibular tract, explaining the lower incidence of hyperprolactinemia than with typical antipsychotic agents or risperidone.||