Provides detailed information on all sleeping pills & minor tranquillisers currently available in the UK.
Promethazine (Phenergan, Sominex) is an antihistamine sometimes used as a sleeping pill. It's available to buy without a prescription from a doctor. It is also an ingredient in some over-the-counter cold and flu medicines, such as Night Nurse.
You can find detailed information about promethazine in the official Patient Information Leaflet (PIL), including what it's for, how to take it, possible side effects and safety information. This leaflet should come with your medication (usually inside the box).
All PILs are available online on the electronic Medicines Compendium (eMC).
If a drug can come in different forms (such as tablets or liquid), there may be a separate PIL for each one. You should look at the PIL for the particular form and dose you've been prescribed.
If you have any questions about your medication you can talk to your doctor, someone at your pharmacy or call NHS 111.
This information was published in April 2017.
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