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Phenergan 25mg (Promethazine Hydrochloride) - 56 Tablets

Based on 1087 reviews
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25mg - 56 Tablets £9.99 check
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Alexandra Smith - Senior Medical Writer
Alexandra Smith
Senior Medical Writer
25/03/2025
24/03/2027
James O'Loan - CEO & Prescribing Pharmacist
James O'Loan
CEO & Prescribing Pharmacist
2084549

Buy Phenergan 25mg (Promethazine Hydrochloride) 

Phenergan 25mg (Promethazine Hydrochloride) tablets are designed to treat a range of conditions, including allergic reactions like hay fever and rashes, travel sickness and insomnia. As a drowsy antihistamine belonging to a group of medicines known as phenothiazines, it works by blocking histamine, the natural substance your body produces during an allergic reaction. This helps to reduce symptoms like itching, swelling and irritation. Phenergan also acts on the brain to promote relaxation, making it effective for relieving nausea caused by travel sickness and encouraging restful sleep. 

Phenergan directions

Always take Phenergan 25mg exactly as described in the patient information leaflet or as your doctor / Chemist4U pharmacist has told you.

For allergies such as hay fever, hives and rashes:

Children over 10 years old and adults: Start by taking 1 tablet at night. If necessary, you can increase the dose to 2 tablets a day.

Children between 6-10 years old: 1 tablet should be given at night. Do not give your child more than 1 tablet a day.   

For nausea and vomiting:

Children over 10 years old and adults: Take 1 tablet the night before a journey. If required, you can take another dose 6-8 hours after the first.

A short-term sedative for insomnia in adults:

1-2 tablets should be taken at night.

Phenergan side effects

Like all medicines, Phenergan 25mg may cause side effects in some people, but these won’t affect everybody. Common side effects may include:

  • Drowsiness
  • Dizziness
  • Headaches 

To see the full list of side effects, including any potentially serious side effects, please refer to the patient information leaflet.

Phenergan warnings

Phenergan 25mg may be unsuitable for certain people. Do not take these tablets if you are allergic to any of the ingredients or if you suffer from severe dizziness, drowsiness or headaches.

Talk to your doctor or Chemist4U pharmacist before taking this medicine if: 

  • You have asthma or bronchitis 
  • You have epilepsy
  • You have any severe heart problems or a family history of heart disease
  • You have an irregular heartbeat 
  • You have kidney problems 
  • You have liver problems 

Using/taking other medicines

If you are taking or have recently taken any medication, including medication obtained without a prescription, talk to your GP or pharmacist before taking this product.

Age restrictions 

Phenergan 25mg is not suitable for children under 6 years old.

Pregnancy and breastfeeding

This medication should not be taken 2 weeks before you are due to give birth. Do not take this product while you are breastfeeding. 

Alcohol

Do not drink alcohol whilst you are taking this medication.

Driving and operating machinery 

This product can make you feel drowsy. If you are affected, do not drive or operate machinery until you feel safe enough to do so.

Storage information

Store below 25°C in a cool, dry place, away from light and 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.

 

Phenergan 25mg (Promethazine Hydrochloride) - 56 Tablets Reviews

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By Jackie,
March 10, 2026
I was able to purchase these at my local pharmacy but since moving the chemist here doesn't sell. So felt confident to purchase from Chemist4U as have used them for other items before. I use this product very occasionally when in a severe cycle of insomnia and one tablet certainly helps me get a good night's sleep
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By Hilary McLaughlin,
March 10, 2026
Recommended by my doctor. Is working great for me.
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By Martina,
March 10, 2026
I use it to manage my sleep issues and it helps. It is not strong, but it helps sometimes. First week, works like magic. Then your body gets used to it and so it does not work as good.
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By B Virdi,
March 10, 2026
This works very well on my allergies
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By Kathryn Konrad,
March 10, 2026
Excellent product. Reasonably priced

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