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Promethazine treats the symptoms of hay fever, allergies and sleeping problems in adults. It falls under the category of sedating antihistamine. It is an effective treatment for allergy symptoms and may minimise the impact of sleeping issues as a result of severe allergies or itching.
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Promethazine treats the symptoms of hay fever, allergies and sleeping problems in adults. It falls under the category of sedating antihistamine. It is an effective treatment for allergy symptoms and may minimise the impact of sleeping issues as a result of severe allergies or itching.


Promethazine belongs to a group of medicines known as phenothiazine medications. Promethazine reduces the symptoms of hives, hay fever and allergies. Promethazine is an antihistamine medication.

This medication works to stop the effects of naturally occurring chemical called histamine in the human body. In conditions wherein you cannot sleep due to an excessive allergic reaction, such as a skin rash, cough, cold, runny nose, sneezing or itching, Promethazine helps you to control your allergy symptoms and aids sleep.

Promethazine reduces the symptoms of allergies, hay fever, and hives (urticaria). Promethazine is an antihistamine medication. Here are some primary uses of this medication.

  1. Prevention/treatment of nausea and vomiting due to motion sickness or before/after surgery.

  1. To treat allergy symptoms such as rash, itching and runny nose.

In the case of an allergic reaction, the human body produces histamine. Histamine is a naturally occurring chemical that helps the body generate allergy symptoms such as rash, itchiness of the skin, runny nose, cough, sneezing, etc. Histamine also makes the brain more alert and awake.

Promethazine is an antihistamine that dulls the effects of histamine on your brain. This medicine helps in symptom control and causes drowsinessPromethazine belongs to the category of medications known as phenothiazine. These medicines are beneficial for the treatment of allergies and allergic symptoms.

Promethazine tablets are an effective medication to relieve the symptoms of allergies such as hay fever. There are various benefits of taking Promethazine. Some of them are listed below.

  • Promethazine is a sedating antihistamine. It helps bring a calming effect to allergies, relieve pain and helps you sleep.

  • It helps you rest by resolving any short-term sleep problems (insomnia) or allergy symptoms such as cough, cold or itching that may be interrupting your sleep.

  • It helps to treat allergies such as hay fever and hives (urticaria).

  • Promethazine cures nausea caused by motion sickness or vertigo.

  • Promethazine helps to treat allergy mediated cough symptoms such as runny nose or sneezing.

Promethazine should be taken as per your doctor's advice. Depending upon the reason why you have been asked to take Promethazine, the dose may differ. This medication is available in strengths of:

  • Promethazine Hydrochloride 10mg

  • Promethazine Hydrochloride 25mg

Usually, the recommended Promethazine dosage is as follows:

  1. Hay Fever – Promethazine 10mg twice a day.

  1. Hives – Promethazine 10mg twice a day travel Sickness – Promethazine Hydrochloride 25mg tablet taken one or two hours before a short journey or Promethazine 25mg taken the night before a long journey.

  1. Nausea & Vertigo – dose can vary between Promethazine 25mg once a day to Promethazine Hydrochloride 25mg tablets two times a day. 

Take Promethazine as per the advice of our team. The number of doses and the quantity may differ according to the condition being treated. Here are some general rules to follow when taking Promethazine.

  • Take Promethazine at bedtime or before meals.

  • When taking Promethazine for travel sickness, take the dose one hour before travelling.

  • To help with sleep, take the medication twenty to thirty minutes before bed.

Some key facts that you should know before taking Promethazine are listed below.

  1. Alcohol can increase the risk of side effects of Promethazine. Avoid drinking alcohol when taking Promethazine.

  1. Promethazine takes up to 30 minutes to take effect.

  1. The different brand names of Promethazine are AvominePromethazine, Phenergan and Sominex.

Just like any other medication, some side effects have been associated with Promethazine. Generally, the observed Promethazine side effects are not severe or harmful. Some of the possible side effects associated with Promethazine are: 

  1. Headache

  1. Dry mouth

  1. Restlessness

All adults and children above the age of 2 years can take Promethazine. However, in some cases, Promethazine may not be a suitable medication. Here are some situations wherein Promethazine is not recommended:

  • You are allergic to Promethazine or any of the ingredients in the medicine

  • You have had an eye problem known as primary angle-closure glaucoma

  • You have urinary problems related to passing urine or emptying your bladder

  • You have epilepsy or any other health issue that causes fits

  • You are lactose or sorbitol intolerant

  • You are having allergy testing at the moment

  • You are pregnant or are trying to get pregnant

  • You have liver or kidney problems

  • You have prostate-related problems

  • You have a blockage in your small intestines

  • You have had breathing problems for a long time, such as chronic obstructive pulmonary disorder (COPD)

  • You are taking other medications that may interact with Promethazine and reduce its effectiveness or vice versa

  • You have a cardiac arrhythmia

Promethazine tablets may interact with other medications to reduce their effectiveness and vice versa. Therefore, it is essential to discuss your on-going treatments, drugs and medical history with our team at the time of consultation. Here are some medicines that are known to interact with Promethazine:

  1. Antidepressants such as monoamine oxidase inhibitors, e.g. phenelzine.

  1. Any other medication that makes you drowsy gives you a dry mouth or makes it difficult for you to urinate. Taking Promethazine, along with these medicines, can make these side effects worse.

Store Promethazine in a cool, dry place away from direct heat or sunlight. Keep all the medicines out of sight and reach of children.

You can buy Promethazine safely in the UK from MedsNow online clinic. Place the order for the medication from the convenience of your home. You may also take an online consultation with our team. The medicine is delivered discreetly to your doorstep.

  1. Can I Drive After Taking Promethazine Tablets?

    Promethazine can make you feel sleepy or drowsy. If this happens, it is not advisable to drive a car, ride a bicycle or operate machinery.

  2. Can I Take Promethazine Tablets If I'm Pregnant or Breastfeeding?

    If you are pregnant, take Promethazine only after consultation with your doctor. They will tell you the appropriate dosage to avoid any side effects for the baby. This is especially crucial if you have two weeks or less left to go before your due date.

  3. Can I Drink Alcohol While I'm Taking These Promethazine Tablets?

    No, Promethazine has a sedative effect. It can make you drowsy or sleepy. It is not advisable to drink alcohol when taking Promethazine as alcohol can make the drowsiness worse.

  4. How Is It Different From Other Cough And Cold Remedies?

    When Promethazine is prescribed for cough and cold, it inhibits the effects of the natural chemical acetylcholine. Due to this, your cough and runny nose get dried up. This effect is very different from other cough and cold remedies – that work by suppressing the cough or stopping phlegm production. Take an online consultation with our team to discuss your needs further.

  5. Does Promethazine Have Codeine?

    No, this treatment does not include codeine.

  6. How Long Does Promethazine Hydrochloride Take To Work?

    Twenty minutes after taking Promethazine, you will feel drowsiness coming on, and the effects of the medication last for twenty hours. If you are taking Promethazine for controlling the symptoms of allergy or nausea. In that case, your symptoms will begin to reduce after twenty minutes and the effects of the medication usually last for four to six hours.

  7. How Long Can I Take It For?

    It is recommended to take Promethazine for a short time only. Talk to our team about how long you can safely take Promethazine.
  8. Is Promethazine Addictive?

    It is improbable to get addicted to Promethazine but it is still recommended that you should only take Promethazine for a short time when needed.

    If you feel the need to take Promethazine for a longer time than recommended on the pack, consult our team to ensure that it is safe and required for your condition.

    If you have been taking Promethazine for a long time and wish to stop – do it gradually by reducing the dose over a few days. Otherwise, you may experience dizziness or feel sick. You may also feel sweaty, have a racing heart or have trouble sleeping.

  9. What's The Difference Between Promethazine Hydrochloride And Other Antihistamines?

    Promethazine is categorized as a drowsy or sedating antihistamine as it makes you sleepy. Various other antihistamine medications do not make you tired or sleepy. Some examples of non-drowsy antihistamines are cetirizine, fexofenadine and loratadine.

    Most people prefer non-drowsy antihistamines as they are more convenient and do not interfere with their day-to-day activities.

    However, if your allergy symptoms such as cough or itchiness of your skin keep you awake at night, it may be a good idea to opt for a drowsy antihistamine such as Promethazine.

    Take online consultation on MedsNow to understand which antihistamine works best for you.

  10. Can I Take Promethazine Tablets With Painkillers?

    Yes. You can safely take Promethazine with painkillers such as paracetamol or ibuprofen. Taking Promethazine with painkillers that contain codeine may make you feel tired and sleepy for many hours.
  11. Can I Drive Or Ride A Bike With Promethazine Tablets?

    It is not advisable to drive a car when taking Promethazine tablets. Promethazine can make you drowsy or sleepy during the daytime. You may also feel dizzy, clumsy or confused when you first begin taking the medication. Avoid driving if possible.
  12. Will Promethazine Tablets Affect My Contraception And Fertility?

    Promethazine does not have any effects on fertility in men or women. If you are trying to get pregnant, consult our team before taking Promethazine.

    You can also safely use contraception when taking Promethazine. This medication does not interfere with the effects of the combined pill or the emergency contraceptive pill.

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