• Phenergan
  • Phenergan


From £7.99

Medication features


  • Contains an antihistamine
  • Often used for Insomnia, Travel Sickness, Allergies
  • 10mg or 25mg Tablets

NOTE: After requesting this medication, you will need to complete a short assessment, so our GP or Pharmacist can assess if the treatment is suitable for you. Pricing is provided as a reference only. The final decision on issuing this medication remains with our GP / Pharmacist.


Phenergan Tablets

Phenergan tablets contain the antihistamine Promethazine, and this can be used to treat a range of ailments, including

  • Allergies
    • Hay fever or other allergic reactions
  • Insomnia
    • for short term relief of sleep disturbances
  • Rashes
    • for red itchy rashes and skin conditions
  • Travel Sickness
    • relief from nausea for people who don't travel well!

How to take Phenergan

Depending on what you are using Phenergan for, the dosage will vary. You may also vary your dose depending on the response, but this should be done according to the patient information leaflet, or on your doctor's advice. 

Below is a summary of the most common uses of Phenergan and the corresponding dosages.


When taken for Insomnia, the usual dose of Phenergan is 25mg taken ONCE daily at NIGHT. You should take this around one hour before bedtime. Phenergan is intended for short term use only when treating insomnia, so if your symptoms go on for longer than 3 nights, see your GP.

Hay Fever

Those taking Phenergan for hayfever generally use the 10mg tablet, and this is taken 2-3 times daily depending on symptom control. Many hayfever sufferers prefer non-drowsy anti-histamines however, as these are less likely to impact your alertness during the day. These include Cetirizine and Loratadine.

Travel Sickness

The dosage of Phenergan, when used to prevent travel sickness, is generally one 25mg tablet taken about 60 minutes before travel. This gives the drug enough time to be absorbed into your system and get to work! Promethazine can be very effective in reducing nausea felt in those travelling by land, air or sea.


What is Phenergan?

Phenergan is an antihistamine medication which is used in a variety of ailments such as allergies, insomnia, travel sickness and itch relief.

What are the side effects Phenergan?

Phenergan tablets can cause the following side effects. Although not everyone will suffer these since every person responds to medication differently.
  • Drowsiness
  • Dizziness
  • Headaches
  • Nightmares
  • Blurred Vision
  • Dry Mouth

How does Phenergan work?

Phenergan tablets contain an antihistamine called promethazine. Antihistamines work by blocking the histamine receptors in your brain. Histamine is responsible for trigger inflammatory processes in the body which can cause redness and inflammation.

Can I drink alcohol when taking Phenergan?

Alcohol should be avoided when taking this medication, as this could worsen the effects of drowsiness.

How long can I take Phenergan for?

Phenergan should not be taken for more than 10 days without advice from your doctor.

Is Phenergan addictive?

Phenergan is not addictive in the way other sleeping tablets may be. However, it is not advisable to take long term for sleep disorders as you may develop an unhealthy reliance on its use. For sleep disturbances which last for more than 3 nights, see your doctor for advice. 

Can I take Phenergan with pain killers?

Yes, it's okay to take Phenergan with pain killers which are available over the counter such as paracetamol (Panadol), and Ibuprofen (Nurofen). Some pharmacy medicines however may also contain codeine or dihydrocodeine. These pain killers can cause drowsiness, and if taken with Phenergan can increase effects of drowsiness experienced. Until you know how these medicines affect you, avoid driving or using machinery.

Side Effects

Side effects of Phenergan

As with any medication, side effects are a possibility when using this medicine. The active ingredient Promethazine can cause the following side effects. 
  • Drowsiness
  • Dizziness
  • Headaches
  • Nightmares
  • Blurred Vision
  • Dry Mouth

More serious side effects include yellowing of your skin / eyes. If this happens to you, seek medical advice, as this could indicate there are problems with your liver. Another more serious side effect is if you notice excessive bruising or bleeding while using Phenergan. Again, this should be reported to your GP. Another reportable side effect is if you experience shaking or severe stiffness in your muscles, or involuntary movements in other parts of your body, particularly your face. 

Finally, should you experience an anaphylactic reaction to Phenergan, seek immediate medical attention. Symptoms of this include difficulty breathing, severe swelling of your tongue, lips or face and severe rashes which may blister or peel.


Info Leaflet

Before taking any medication, it is important to read the Patient Information Leaflet. You can find information leaflets for your medicines by typing them into the search bar at, or by contacting us.

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