Veterinary Drug Handbook (VDH) is the reference veterinarians turn to when they want an independent source of information on the drugs that are used in veterinary medicine today.


Chemistry - A propylamino phenothiazine derivative, promazine is structurally identical tochlorpromazine, but lacks the chlorine atom at the 2 position of the phenothiazine nucleus. It occursas a bitter tasting, practically odorless, white to slight yellow crystalline powder. Promazine is freelysoluble in alcohol and 333 mg are soluble in 1 ml of water at 25°C. The commercial injection has apH from 4-4.5 and is dissolved in a solution of sterile water for injection.

Storage, Stability, Compatibility

Protect from prolonged exposure to air, protect from light, andstore from 15-30°C. Avoid freezing the injectable product.
Upon prolonged exposure to air, promazine will oxidize and change to a pink or blue color. Donot use the injectable product if color changes (a slight yellowish tint is OK), or a precipitate forms.
The following products have been reported to be compatible when mixed with promazine injection: All usual intravenous fluids (except Ionosol B with Dextrose 5% or isotonic sodium bicarbonate), atropine sulfate, chlorpromazine HCl, chloramphenicol sodium succinate, diphenhydramine, droperidol, fentanyl citrate, glycopyrrolate, heparin sodium, hydroxyzine HCl, lidocaine
HCl, meperidine, metoclopramide, metaraminol bitartrate, morphine sulfate, pentazocine lactate, promethazine, scopolamine HBr, & tetracycline HCl.
The following products have been reported as being incompatible when mixed with promazine:
Ionosol B with dextrose 5%, aminophylline, chlorothiazide sodium, dimenhydrinate, fibrinogen, fibrinolysin (human), methohexital sodium, nafcillin sodium, penicillin g potassium, pentobarbitalsodium, phenobarbital sodium, sodium bicarbonate (is reportedly compatible when 100 mg/l ofpromazine mixed with 2.4 mEq/l of bicarb in D5W), thiopental sodium, and warfarin sodium.
Compatibility is dependent upon factors such as pH, concentration, temperature and diluents used.
It is suggested to consult specialized references for more specific information (e.g., Handbook on
Injectable Drugs by Trissel; see bibliography).

Pharmacology - PROMAZINE HCL

Promazine has pharmacologic actions similar to acepromazine; refer to thatmonograph for a more detailed discussion of phenothiazine actions in animals.

Uses, Indications

Used basically for the same purposes as acepromazine; refer to that monograph for more information. Promazine is approved for use in dogs, cats, and horses.

Pharmacokinetics - PROMAZINE HCL

Promazine is absorbed when given orally to non-ruminants; the drug is alsoapparently absorbed to some extent in ruminants when oral granules are used as they have someefficacy. In the dog, the onset of action following an IV dose is usually within 5 minutes, andfollowing an IM dose within 30 minutes. Onsets of action reportedly are slightly longer in largeanimal species after parenteral administration. In horses, the onset of action after the oral granuleshave been consumed average around 45 minutes. The duration of action of promazine has beendescribed as being dose-dependent, but generally ranges between 4-6 hours.
Promazine is metabolized in the liver primarily to glucuronide conjugates and these are excretedby the kidneys. In the horse, promazine metabolites are not detectable in the urine 72 hours after thelast dose.
Contraindications/Precautions - Refer to the monograph for acepromazine for more information. Additionally, there are reports of horses being unusually sensitive to noise and reacting violently to sudden stimulation.

Adverse Effects, Warnings

Refer to the monograph for acepromazine for more information.
Overdosage - Refer to the monograph for acepromazine for more information.

Drug Interactions

Refer to the monograph for acepromazine for more information.

© 2011-2021 Veterinary Terms, Diagnoses and Drug Handbook Online

Wait 20 seconds...!!!