What is Promethazine hydrochloride - Meaning and definition

Published by Roberto Wenk. Reviewed by Alison Ramsey. Last updated date: January 29, 2019.

The hydrochloride salt form of promethazine, a phenothiazine derivative with antihistaminic, sedative, and antiemetic properties.
Promethazine hydrochloride selectively blocks peripheral H1 receptors, thereby diminishing the effects of histamine on effector cells.
Promethazine hydrochloride also blocks the central histaminergic receptors, thereby depressing the reticular system, causing sedative and hypnotic effects.
In addition, promethazine hydrochloride also has centrally acting anticholinergic properties and probably mediates nausea and vomiting by acting on the medullary chemoreceptive trigger zone.

National Cancer Institute. NCI Drug Dictionary. Internet. September 15, 2009.

Published by Roberto Wenk. Last updated date: February 15, 2016.

Adult
PO
Allergic conditions - HCl: 25 mg at night, up to twice daily if needed.
Nausea and vomiting - teoclate: 25 mg at bedtime, up to 50 or 75 mg at night or 25 mg 2-3 times/day if needed. Max: 100 mg/day.
Insomnia - HCl: 20-50 mg/day at night.
Prevention of motion sickness - HCl: 20 or 25 mg the night before travelling followed by a similar dose in the morning if needed. As teoclate: 25 mg at night or 1-2 hr before travelling.

IV/IM
Allergic conditions - HCl: 25-50 mg. Max: 100 mg.
Nausea and vomiting - HCl: 12.5-25 mg, may repeat at intervals of not <4 hr. Max: 100 mg/24 hr.

Adverse drug reactions: CNS depression, paradoxical excitation in children, dryness of mouth, blurring of vision, retention of urine, constipation, glaucoma, tachycardia, headache, hypotension.

Adapted from CIMS Drug Information System. Internet. Accessed on January 10, 2016.

To cite

Promethazine hydrochloride. IAHPC Pallipedia. https://pallipedia.org/promethazine-hydrochloride. Accessed