Top Gene Interactions
- Metabolism: Hepatic, primarily to N-desmethylpromazine and promazine sulfoxide. Absorption may be erratic and peak plasma concentrations show large interindividual differences. The metabolism occurs through oxidative processes mediated largely by hepatic microsomal and other drug metabolizing enzymes. Antoher step is the conjugaion with glucuronic acid. Other reactions include hydroxylation, demetylation, and sulfoxide formation. Moreover, metabolic alterations in side chain may also occur (A308, A631).
- Uses/Sources: Used as an adjunct for short term treatment of moderate and severe psychomotor agitation. Also used to treat agitation or restlessness in the elderly.
- Health Effects: It has predominantly anticholinergic side effects, though extrapyramidal side effects are not uncommon either. Other effects include endocrine effects (such as gynaecomastia and menstrual disturbance), sensitivity to sunlight and haemolytic anaemia (A308, L1149).
- Symptoms: Side effects include: extrapyramidal symptoms, drowsiness, weight gain, dry mouth, constipation, endocrine effects (such as gynaecomastia and menstrual disturbance), sensitivity to sunlight and haemolytic anaemia.
- Treatment: In severe cases, consider supportive therapy. Maintain clear airway and adequate hydration. Anti-Parkinson drugs, as well as benztropine mesylate, and barbiturates can be use to relieve extrapyramidal symptoms (A632).
- Route of Exposure: Inhalation; dermal or skin contact; ingestion (MSDS, A308). Absorption may be erratic and peak plasma concentrations show large interindividual differences.
- Carcinogenicity: No indication of carcinogenicity to humans (not listed by IARC).
- Toxicity: LD50: 140 mg/kg (Intraperitoneal, Mouse)
Mechanism of Action
|Target Name||Mechanism of Action||References|
Alpha-2A adrenergic receptor
Solute carrier family 22 member 1
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
|Promazine is an antagonist at types 1, 2, and 4 dopamine receptors, 5-HT receptor types 2A and 2C, muscarinic receptors 1 through 5, alpha(1)-receptors, and histamine H1-receptors. Promazine'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. Promazine does not appear to block dopamine within the tubero-infundibular tract, explaining the lower incidence of hyperprolactinemia than with typical antipsychotic agents or risperidone. Antagonism at muscarinic receptors, H1-receptors, and alpha(1)-receptors also occurs with promazine.||
Promazine Interacts with Diseases
|Disease||Inference Score||References/Inference Genes|
|ACTH Deficiency, Isolated||6.12||
|Sleep Apnea Syndromes||5.62||
|Stereotypic Movement Disorder||4.89||