If you are wondering whether you can crush promethazine (Phenergan) tablets, the simple answer is that you should not crush or chew them unless a pharmacist or prescriber has advised you to do so. NHS guidance says promethazine tablets should be swallowed whole with a drink of water. The specific Phenergan 25mg tablet is film coated and is not described as a scored tablet in the UK product information.
If you have difficulty swallowing tablets, promethazine is also available as an oral liquid. Phenergan Elixir contains 5mg of promethazine in each 5ml and may be a more suitable option for people who cannot swallow tablets. A pharmacist can advise whether the liquid is appropriate for you.
This guide is for adults in the UK who have been prescribed or advised to take promethazine and want clear information about how to use it. It covers tablets and liquid, missed doses, how often promethazine is taken, and important safety points.
Key things to know
- UK Phenergan 25mg tablets are film coated and should be swallowed whole rather than crushed or chewed
- Promethazine is also available as a liquid containing 5mg in 5ml
- You can take promethazine with or without food
- The dose and timing depend on why you are taking it, so follow the instructions on your prescription or medicine packaging
- Promethazine can make you sleepy or dizzy, so avoid driving if you are affected
- Do not drink alcohol while taking promethazine because it can increase its sedating effects
Can You Crush Promethazine Tablets?
NHS guidance says to swallow promethazine tablets whole with a drink of water and not to chew them. The UK Phenergan 25mg tablet is film coated and is not described as having a score line in its product information.
Because of this, do not crush or alter the tablet unless a pharmacist or prescriber specifically tells you that it is suitable to do so.
If you find tablets difficult to swallow, ask about the liquid formulation instead. Phenergan Elixir contains 5mg in 5ml and can be measured using an oral syringe or measuring spoon.
Can You Split Promethazine Tablets?
It is best not to split a Phenergan tablet unless a pharmacist or prescriber has told you to do so.
A tablet without a score line is not designed to provide two measured halves. If you need a different dose, do not try to create one by breaking the tablet yourself. A pharmacist can check whether a different tablet strength or the liquid formulation would be more suitable.
The available strengths and doses can vary between promethazine products, so always check the specific medicine you have been given.
How to Take Promethazine Tablets for Motion Sickness
If you are taking promethazine for motion sickness, follow the instructions for your specific product. NHS guidance says adults and children aged 10 years or over will usually take 25mg for prevention, often the night before a journey. Some products can be taken 1 to 2 hours before a short journey instead.
For the Phenergan 25mg tablets specifically, the product information says adults and children over 10 years can take 25mg the night before a journey, with another dose after 6 to 8 hours if required.
For general tablet use:
- Swallow the tablet whole with a drink of water
- You can take promethazine with or without food
- Follow the dose and timing on your prescription or the medicine packaging
- Do not take an extra dose to make up for a missed dose
- Do not crush or chew the tablet unless a pharmacist or prescriber has advised you to do so
How to Take Promethazine Elixir
If you are using promethazine liquid:
- Shake the bottle if the product instructions tell you to do so
- Use the oral syringe or measuring spoon supplied with the medicine
- Do not use a household teaspoon because it may not measure the correct amount
- Check the label carefully for the amount you have been told to take
- Phenergan Elixir contains 5mg of promethazine in each 5ml
- Store the medicine according to the instructions on the packaging
Phenergan Elixir should not be used for longer than 7 days without medical advice. The product information also states that the bottle should not be used more than one month after opening.
Can You Take Promethazine on an Empty Stomach?
Yes. Promethazine can be taken with or without food. There is no general requirement to take it on an empty stomach.
If you find that it upsets your stomach, taking it with food may be more comfortable. If you have been given specific instructions by your doctor or pharmacist, follow those instead.
How Often Should You Take Promethazine?
It depends on why you are taking it and which promethazine product you have.
For example, NHS guidance gives different schedules for allergies, motion sickness and vertigo. Adults taking promethazine for hay fever or hives may be advised to take it more than once a day, while motion sickness usually involves a dose before travelling and further doses only when needed.
For Phenergan 25mg tablets, the product information gives different doses depending on whether it is being used for allergies, nausea and vomiting, or short term insomnia.
This is why there is no single number of hours that applies to everyone. Follow the instructions on your prescription or medicine packaging. If you are unsure how to space your doses, ask a pharmacist rather than guessing.
How Long Should You Take Promethazine For?
Promethazine is generally intended for short term use unless a doctor advises otherwise.
The UK Phenergan product information says it should not be used for longer than 7 days without seeking medical advice. This applies to both the tablet and elixir formulations.
If you are taking promethazine for allergies, motion sickness or another condition and need it for longer, follow the advice given by your doctor or pharmacist.
If you have questions about how to take Phenergan 25mg tablets or the elixir, a pharmacist can help.
Important Safety Information and Allergic Reactions
- Phenergan tablets and elixir should not be given to children under 6 years of age. Other promethazine products can have different age restrictions, so always check the specific product.
- Do not take Phenergan if you are taking a monoamine oxidase inhibitor (MAOI), or if you stopped taking one within the previous 14 days.
- Tell your doctor or pharmacist about other medicines you take. Promethazine can increase the sedating effects of medicines such as sedatives, sleeping tablets and some other medicines that affect the central nervous system.
- Do not drink alcohol while taking promethazine. Alcohol can increase its sedating effects and may make you very sleepy.
- Tell your doctor or pharmacist if you have asthma or other breathing problems, epilepsy or seizures, glaucoma, heart problems, liver or kidney problems, or difficulty passing urine.
- Stop taking promethazine and seek urgent medical help if you develop signs of a serious allergic reaction, such as swelling of the face, lips, tongue or throat, or difficulty breathing.
- Promethazine can cause drowsiness, dizziness and reduced alertness. Do not drive, cycle or operate machinery if you are affected.
- Do not crush or chew promethazine tablets. If swallowing is difficult, ask a pharmacist whether the liquid formulation may be suitable.
Genuine Pricing
| Product | Price |
|---|---|
| Phenergan 25mg, 56 tablets | £14.99 |
| Phenergan Elixir 5mg/5ml, 100ml | £14.49 |
Medical Disclaimer
This page provides general information about how to take promethazine. It is not a substitute for personalised medical advice, diagnosis or treatment. Speak with a pharmacist, GP or other healthcare professional if you are unsure about your dose or how to take the medicine.
Do not crush, chew or split promethazine tablets unless a healthcare professional has specifically advised you to do so. If swallowing tablets is difficult, ask about the liquid formulation.
Phenergan should not be used for longer than 7 days without medical advice. Promethazine can cause drowsiness and dizziness, and alcohol can increase its sedating effects. Do not drive or operate machinery if you feel sleepy, dizzy or less alert.
Seek urgent medical help if you develop difficulty breathing, swelling of the face or throat, a severe allergic reaction, a seizure, loss of consciousness or other serious symptoms. If you take more than the recommended dose, seek medical advice even if you feel well.
