Promazine (brand name Sparine among others), is used as a short-term add-on treatment for psychomotor agitation.[1] Its approved uses in people is limited, but is used as a tranquilizer in veterinary medicine.[1] It has weak antipsychotic effects but is generally not used to treat psychoses.[1]
It acts similar to chlorpromazine and causes sedation.[1] It has predominantly anticholinergic side effects, though extrapyramidal side effects are not uncommon. It belongs to the typical antipsychotic and phenothiazine class of drugs.[2]
Promazine was approved for medical use in the United States in the 1950s, although it is no longer commercially available there.[3] [4]
Promazine is a short-term add-on treatment for psychomotor agitation.[5]
Common side effects include agitation, amenorrhea, arrhythmias, constipation, drowsiness and dizziness, dry mouth, impotence, tiredness, galactorrhoea, gynecomastia, hyperglycemia, insomnia, hypotension, prolonged QT, seizures, tremor, vomiting and weight gain, among others.[5]
In overdose, it may cause hypotension, hypothermia, tachycardia, and an arrythmias.[5]
Sudden death may occur, although rare.[5]
Promazine, given as promazine hydrochloride, is one of the primary tranquilizers used by veterinarians as a pre-anaesthesia injection in horses.[6] [7] It does not provide analgesia and is not a very strong sedative, hence it is used combined with opioids or α2 adrenoreceptor agonists, such as clonidine, or both.[7] [8] It can be used alone when performing a non-painful procedure such as the fitting a horseshoe.[8] Low blood pressure, fast heart rate and paralysis of the penis are side effects.[6] It is also an antiemetic, antispasmodic and hypothermic agent.[7] Additionally it is used to lower blood pressure in animals with laminitis and kidney failure.[7] It is available in the US for veterinary use under the names Promazine and Tranquazine.