Promethazine
Uses of Promethazine
Promethazine is commonly used in the treatment of motion sickness, vertigo, hay fever, urticaria, pruritis, angioedema, rhinitis, conjunctivitis and insomnia.
How Promethazine Works
Promethazine works by inhibiting the postsynaptic mesolimbic dopaminergic receptors in the brain which produces the α-adrenergic blocking effect and suppresses the release of hypothalamic and hypophyseal hormones. Antiemetic activity will be produced through muscarinic blocking and also it competes with histamine to bind with H1-receptor
Side Effects of Promethazine
Bradycardia, Tachycardia, Hypotension, Jaundice, Neuroleptic Malignant Syndrome (NMS)
Warnings
Kidney Use With Care
Promethazine should be used with caution in patients with kidney impairment. Dose adjustment of Promethazine may be needed. Please consult your doctor.
Alcohol Not Advisable
It is not advisable to drink alcohol with Promethazine as it enhances the CNS effects of the Alcohol.
Pregnancy Not Safe
Promethazine may be unsafe to use during pregnancy. Animal studies have shown side effects on the fetus, however, there are limited human studies. The benefits from use in pregnant women may be acceptable despite the risk. Please consult your doctor.
Driving Not advisable
Do not drive unless you are feeling well. Promethazine may cause side effects such as marked drowsiness which could affect the ability to concentrate and drive.
Liver Use With Care
Promethazine should be used with caution in patients with liver disorder. Dose adjustment of Promethazine may be needed. Please consult your doctor.
Lactation Not Advisable
Promethazine is shown to be excreted in breast milk. It is not advisable for women to breastfeed while consuming Promethazine because of its potential adverse drug effects on infants.
Frequently Asked Questions
Written by Dr Sri Viknarajan, MD (Universiti Hasanuddin, Indonesia)
Reviewed by Dr Nur Syuhada binti Zulkifli, MD, Universiti Kebangsaan Malaysia (UKM).
