antihistamine medication
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Promethazine tablets are used to treat allergy symptoms, insomnia and travel sickness. This is an antihistamine medication that can relieve a variety of symptoms caused by common allergies as well as fighting sleeplessness and nausea that often arise when travelling.
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Jordan Christchurch reviewed
"Fast, easy to use and very responsive customer service. Prices are also very competitive."
RJ Layton reviewed
"5 Start service is so much easier than going to my local pharmacy, especially when feeling under the weather."
Bianca Carthright reviewed
"No fuss, and fast delivery. Welzo dispatched my order the same day and it arrived in the morning."
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What is Promethazine?

Promethazine is a drug used for the treatment of travel sickness, insomnia and symptoms of allergic reactions, e.g., skin rashes, hives, watery eyes, sneezing, running nose, itching etc. 

How does it work?

Promethazine is a member of the phenothiazine class of drugs. It exerts its effects by blocking the histamine receptors. The histamine is produced in your body in response to allergic reactions and causes most of the symptoms associated with allergic reactions. It also blocks the receptors involved in sleep, tension and anxiety. 

Is Promethazine suitable for me?

It is suitable for adults and children above 6 years old with signs of allergic reactions, travel sickness and insomnia. However, for younger children, it should only be used with a prescription from a doctor. It can cause serious and fatal reactions for 2 years or fewer babies. Strictly follow the instructions of the doctor for its use.

The product images shown may represent the range of products, or be for illustration purposes only and may not be an exact representation of the product.

Side Effects

All medications can cause potential side effects, below we have listed some potential side effects, however, these do not always occur. The common side effects are;

  • Insomnia and tiredness
  • Dry Mouth
  • Nervousness
  • Double vision
  • Ringing sensation in the ears
  • Dizziness
  • Drowsiness

In case of allergic reactions, stop taking it and immediately seek medical assistance. 

Disclaimer: This website does not constitute as medical advice, you should also consult with a doctor before taking medication. If you experience any major reactions to any medication you are taking, you must seek immediate medical attention.


Commonly used dosage guidelines for Promethazine.

The dosage of oral Promethazine depends upon the purpose of its use.

For allergic reactions

  • For adults, the dose is 12.5mg before meals or 25mg at bedtime, as recommended by the doctor. 
  • The recommended dose for children (2 years and above) is half of the adults. However, the doctor will decide according to health and weight. 
  • For infants, use only on the recommendation of a doctor. 

As a preventive treatment for travel sickness

  • For adults, the dose is 25mg twice daily. Take the initial dose a few hours before travelling and repeat it 8-12 hours later. You can repeat it if needed on the next day of the journey.
  • The dose for children is 12-25mg, with the same usage guidelines as for adults. 
  • For infants, the dose should be decided by the doctor.

For pain killing and sedation 

  • The dose is 25-50mg, and the doctor should recommend the pattern.

Disclaimer: This website does not provide medical advice. No information listed on this website is intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your physician or other qualified health care provider with any questions you may have regarding a medical condition or treatment before undergoing a new health care regimen, and never disregard professional medical advice or delay in seeking it because of something you have read on this website.


Next Day Delivery Guarantee

All orders placed before 14:00 on weekdays will be delivered the next working day. For the majority of the UK, medication will be dispatched by Royal Mail, Monday to Friday, if ordered before 14:00. Dispatches are sent using Royal Mail's Next-Day Tracked 24-Hour service. We will email you tracking information directly and you should receive your order the day after dispatch.


Our Discreet Packaging Promise

We know that many of our customers turn to us when they need personal medication, preferring to use our online service rather than shopping for the product face to face. That is why our delivery is always discreetly packaged in plain brown boxes or enveloped. You will not have to worry about any content descriptions, and the package will be for your eyes only!

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We will dispatch your order using our express next-day courier service from our pharmacy partners across the UK. You will receive your treatment discreetly to the comfort of your home/ selected address. 

Can Promethazine be used for a cough?

Promethazine induces sleepiness, and you can feel relief from cough symptoms after 20 minutes of use.

What drugs do I need to avoid while taking Promethazine?

Promethazine causes reactions with some drugs, which should be avoided with it. These include;

  • Alcohol
  • Benzodiazepines
  • Opioids

Can Promethazine cause weight gain?

Weight gain is one of the side effects of the long-term use of antihistamines. It is because these drugs affect appetite control mechanisms.

What is the elimination half-life of Promethazine?

Its elimination half-life is 12 hours. It means you must repeat it twice daily, and its effects will vanish in 24 hours.

Can I use Promethazine during pregnancy?

Although limited data is available, it is known to be safe in pregnancy as soon as you can manage the side effects. However, it might interact with some drugs used during pregnancy. So, you should consult with your doctor before use. 

Does Promethazine have narcotic actions?

No. It is not a narcotic. It is used to relieve the symptoms of allergic reactions and can't be used as a pain killer for deep pains.

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