Products
Promazine is commercially available in the form of dragées (Prazine). It has been approved in many countries since 1957.
Structure and properties
Promazine (C17H20N2S, Mr = 284.4 g/mol) is present in drugs as promazine hydrochloride, a white crystalline powder that is very soluble in water. It is a dimethylamine derivative of phenothiazine and structurally belongs to the phenothiazines. It does not contain a chlorine atom in the molecule, unlike chlorpromazine.
Effects
Promazine (ATC N05AA03) has antipsychotic, depressant, sedative, and antiemetic properties. Effects include antagonism at dopamine, muscarinic, histamine, and serotonin receptors and at adrenergic receptors. Promazine has a half-life of up to 35 hours.
Indications
For treatment of psychotic disorders, agitation and restlessness, and relief of nausea and vomiting.
Dosage
As directed in the package insert. Tablets may be administered up to four times daily (every 4 to 6 hours).
Contraindications
- Hypersensitivity
- Comatose states as a result of centrally depressant drugs or alcohol
- Bone marrow depression
- Narrow-angle glaucoma
Full precautions can be found in the drug label.
Interactions
Drug-drug interactions have been described with the following substances:
- Central depressant drugs
- Anticholinergics
- Antacids
- Stimulants
- CYP inducers and inhibitors
Adverse effects
Possible adverse effects include:
- Blood count disturbances
- Hyperglycemia or hypoglycemia
- Appetite and weight gain
- Paradoxical behavior disorders
- Drowsiness, dizziness, headache, dullness.
- Movement disorders, Parkinson’s syndrome
- Malignant neuroleptic syndrome
- Visual disturbances, glaucoma, pigment deposits in the eye.
- Prolongation of the QT interval, cardiac arrhythmias.
- Drop in blood pressure
- Indigestion, dry mouth, constipation.
- Skin reactions
- Urinary retention
- Menstrual cramps, milk flow (women).
- Breast swelling, impotence (men).
