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Sominex One A Night 20mg - 16 Tablets

Based on 28 reviews
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RRP  £4.59
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Alexandra Smith - Senior Medical Writer
Alexandra Smith
Senior Medical Writer
14/05/2025
13/05/2027
Alexandra Smith - Senior Medical Writer
Alexandra Smith
Senior Medical Writer

Buy Sominex One A Night 20mg - 16 Tablets

Sominex tablets contain promethazine hydrochloride, an antihistamine with a calming, sedative effect. This medicine is designed to help you get a good night’s sleep, especially if your usual sleep pattern has been disrupted. 

Sominex can make it easier to fall asleep and stay asleep when changes to your routine, such as travel or shift work, make it challenging to rest properly.

Directions

Always take Sominex exactly as described in the patient information leaflet or as your doctor / Chemist4U pharmacist has told you. For adults and children over 16 years, the recommended dose is one tablet taken at bedtime. 

If you find it difficult to fall asleep, take the tablet up to one hour after going to bed. However, this medicine should not be used for more than seven consecutive days. 

For further information on the directions of Sominex, please refer to the patient information leaflet.

Warnings

  • Do not take these tablets if you are allergic to promethazine or any of the other listed ingredients.
  • Tell your prescriber if you are taking or have taken any other medicines.
  • These tablets are unsuitable for anyone under the age of 16.
  • Sominex should not be taken 2 weeks before birth; do not take if you are breastfeeding. This medicine may impact the results of a pregnancy test.
  • These tablets will cause drowsiness; do not drive or operate machinery.
  • Do not drink alcohol while taking these tablets.
  • These tablets contain lactose and 23mg of sodium per tablet.

Storage information

Store out of sight and reach of children. Do not use after the expiry date, referring to the last day of the month stated on the packaging. Do not throw away any medicines via wastewater or household waste.

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Sominex One A Night 20mg - 16 Tablets Reviews

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By Robert Newman,
November 18, 2025
At last they are available to buy. Good prices a very good and helpful company. You should use them.
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By KAREN KING,
October 15, 2025
It really helps and it neutral which is even better
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By Brian M,
October 07, 2025
These are great tablets when suffering from anxiety or sleeplessness, as they are very effective, but without side effects.
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By Chris Harris,
October 07, 2025
Delighted to be able to buy these again as they disappeared from local pharmacies a couple of years ago. Only use them sporadically but they are handy to have around. Also they are easy to break in half as I don't usually need a full tablet. No nasty side effects (like dry mouth in the morning)
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By Colm Divin,
September 23, 2025
It has been a good and helpful experience

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