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Drug Class
Sedating Antihistamine
Common Uses
- Allergies
- Insomnia
Common Brand Names
Phenergan
Overview
Promethazine is an antihistamine medicine that relieves the symptoms of allergies.
It's known as a drowsy (sedating) antihistamine, so it's more likely to make you feel sleepy than other antihistamines.
Promethazine is used for:
- short-term sleep problems (insomnia) – including when a cough, cold or itching is keeping you awake at night
- allergies, including hay fever and hives (urticaria)
- feeling and being sick (vomiting) – due to motion sickness or vertigo
- cold symptoms, such as coughing and a runny nose
Important Facts
- Do not drink alcohol while taking promethazine. Alcohol increases the risks of side effects.
- To help you sleep, take promethazine 20 minutes before you go to bed. It normally takes about 30 minutes to work.
- To prevent motion sickness, take promethazine the night before a long journey or 1 to 2 hours before a short journey.
- Common side effects of promethazine include drowsiness, headaches, nightmares and feeling dizzy, restless or confused.
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