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Phenergan 25mg Tablets x56

Phenergan 25mg Tablets x56

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  • ✔️ Relieves hay fever, hives, and allergic rhinitis symptoms
  • ✔️ Helps you fall asleep faster with short-term insomnia
  • ✔️ Effective for travel sickness and nausea relief
  • ✔️ 56-tablet pack provides a longer-lasting supply
  • ✔️ Suitable for adults and children aged 5 and over

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What Are Phenergan 25mg Tablets Used For?

 

If you've been struggling with allergy symptoms, travel sickness, or restless nights, Phenergan 25mg tablets are a well-established over-the-counter option worth knowing about. Each tablet contains 25mg of promethazine hydrochloride, a first-generation antihistamine that has been used in the UK for decades. Whether it's a bout of hay fever, an itchy skin reaction, or difficulty nodding off, Phenergan covers a surprisingly broad range of everyday complaints. You can browse our full range of allergy and hay fever treatments if you'd like to compare your options before buying.

This pack contains 56 tablets, making it a practical choice if you need a longer supply. It's available without a prescription, though it's always worth checking with a pharmacist if you're unsure whether it's right for you.

 

How Do Phenergan 25mg Tablets Work?

 

Promethazine works by blocking histamine H1 receptors in the body. When your immune system encounters an allergen — pollen, dust mites, pet dander — it releases histamine, which triggers the familiar symptoms of sneezing, itching, and watery eyes. By blocking those receptors, promethazine reduces the allergic response at its source.

  • Blocks peripheral H1 histamine receptors to reduce allergic symptoms
  • Crosses the blood-brain barrier, producing a sedative effect useful for short-term insomnia
  • Has antiemetic (anti-sickness) properties, making it effective for nausea and travel sickness
  • Anticholinergic action contributes to its drying effect on mucous membranes

Because promethazine does cross into the central nervous system, drowsiness is a notable effect — which is why it's also used as a short-term sleep aid. That sedative quality is a double-edged sword: helpful at bedtime, but something to be mindful of during the day.

 

Who Should Use Phenergan 25mg Tablets?

 

Phenergan 25mg tablets are suitable for a range of adults and older children, but they're not for everyone. They're particularly useful if you need relief from multiple symptoms at once — for instance, allergy symptoms that are also disrupting your sleep.

  • Adults and children aged 5 and over (with appropriate dosing)
  • People experiencing hay fever, urticaria (hives), or allergic rhinitis
  • Those suffering from short-term insomnia linked to allergy or anxiety
  • Travellers prone to motion sickness or nausea

It is not suitable for children under 5 years of age. People with certain conditions — including epilepsy, glaucoma, liver problems, or an enlarged prostate — should speak to a pharmacist or GP before using it. If you're also looking for relief from nausea specifically, our sickness and nausea range has additional options worth considering.

 

How Does Phenergan Compare to Other Antihistamines?

 

Feature Phenergan 25mg (Promethazine) Cetirizine 10mg
Generation First-generation Second-generation
Drowsiness Yes — significant sedative effect Minimal in most people
Uses Allergy, sleep, nausea, travel sickness Allergy and hay fever only
Suitable for driving? No — impairs alertness Generally yes, with caution

 

How Should You Store Phenergan 25mg Tablets?

 

Store your Phenergan 25mg tablets below 25°C in a dry place, away from direct sunlight. Keep them in the original packaging and out of reach of children at all times. Do not use the tablets after the expiry date printed on the pack.

It's worth noting that Phenergan 25mg tablets are a first-generation antihistamine, which means they behave differently to newer alternatives. If you're managing ongoing allergy symptoms and want a non-sedating option for daytime use, speak to your pharmacist about whether a second-generation antihistamine might be more appropriate alongside or instead of this product.

This product is a medicine. Speak to your doctor or pharmacist before using if you have an underlying medical condition or are taking other medicines.

Phenergan 25mg Tablets x56 specifications
Treatment category Allergy, sleep aid, nausea and travel sickness
Mechanism of action H1 histamine receptor antagonist with sedative and antiemetic properties
Effective for Allergic rhinitis, urticaria, short-term insomnia, travel sickness, nausea
Suitable for Adults and children aged 5 and over
Active ingredient Promethazine hydrochloride 25mg
Pack size 56 tablets
Strength 25mg
UK classification P (Pharmacy medicine)
Drug class First-generation antihistamine
Preparation Tablet
Route of administration Oral

Specifications of Phenergan 25mg Tablets x56

 

What Is Phenergan 25mg and What Is It Used For?

 

Phenergan 25mg tablets contain promethazine hydrochloride, a first-generation antihistamine licensed for use in the UK. It is used to treat a range of conditions where histamine plays a role, as well as conditions where its sedative properties are clinically useful. The NHS recognises promethazine as an effective treatment for allergic conditions and short-term sleep problems.

Phenergan 25mg tablets are indicated for:

  • Allergic conditions including hay fever, allergic rhinitis, and urticaria (hives)
  • Short-term insomnia in adults and children aged 5 and over
  • Nausea, vomiting, and travel sickness
  • Itching associated with chickenpox or other skin reactions

 

What Do You Need to Know Before Using Phenergan 25mg?

 

Before taking Phenergan 25mg tablets, it's important to check whether this medicine is appropriate for you. There are several situations where you should not take it, and others where extra caution is needed.

Do not take Phenergan 25mg if you:

  • Are allergic to promethazine or any other ingredient in the tablet
  • Are under 5 years of age
  • Have a condition called porphyria
  • Are taking monoamine oxidase inhibitors (MAOIs) or have taken them in the last 14 days

Speak to your pharmacist or GP before taking if you have:

  • Epilepsy or a history of seizures
  • Glaucoma (raised pressure in the eye)
  • An enlarged prostate or difficulty passing urine
  • Liver or kidney problems
  • Severe heart disease

Known drug interactions — avoid combining with:

  • Alcohol (increases sedation significantly)
  • Other CNS depressants including sleeping tablets, opioids, and anxiolytics
  • Anticholinergic medicines (e.g. some bladder or stomach medicines)
  • MAOIs (risk of serious interaction)
  • Some antidepressants and antipsychotics

 

How Should You Use Phenergan 25mg Tablets?

 

Always take Phenergan 25mg tablets exactly as described in the patient information leaflet or as directed by your pharmacist. Swallow the tablets whole with water. Do not crush or chew them.

  1. Check the dosage table below for the correct dose for your age and condition
  2. Take with or without food — food may help if you experience stomach upset
  3. For sleep: take 20–30 minutes before bedtime
  4. For travel sickness: take the night before travel and again on the morning of travel
  5. Do not exceed the stated dose
  6. Do not drive or operate machinery after taking this medicine
Indication Age Group Dose Frequency
Allergy / hay fever Adults 25mg At night, or 10mg 2–3 times daily
Short-term insomnia Adults 25mg Once at bedtime
Travel sickness Adults 25mg Night before and morning of travel
Allergy / hay fever Children 5–10 years 5–15mg As directed by pharmacist or GP
Short-term insomnia Children 5–10 years 15–20mg Once at bedtime

If you're also managing sleep difficulties alongside allergy symptoms, it may be worth exploring our sleep aid range for additional options.

 

What Are the Possible Side Effects of Phenergan 25mg?

 

Like all medicines, Phenergan 25mg tablets can cause side effects, though not everyone experiences them. The most notable is drowsiness — which is expected and, in some cases, the intended effect.

Common side effects:

  • Drowsiness and sedation
  • Dry mouth
  • Blurred vision
  • Dizziness
  • Headache

Less common side effects:

  • Restlessness or agitation (more common in children)
  • Confusion, particularly in elderly patients
  • Difficulty passing urine
  • Constipation
  • Skin sensitivity to sunlight (photosensitivity)
  • Palpitations or irregular heartbeat

Stop taking Phenergan and seek urgent medical attention if you experience a severe allergic reaction (rash, swelling of the face or throat, difficulty breathing), or any unusual movement disorders.

 

How Should You Store Phenergan 25mg Tablets?

 

Correct storage helps maintain the effectiveness and safety of your tablets. Follow these guidelines:

  • Store below 25°C in a cool, dry place
  • Keep away from direct sunlight and moisture
  • Store in the original packaging until use
  • Keep out of the sight and reach of children
  • Do not use after the expiry date printed on the pack
  • Do not dispose of medicines via wastewater or household waste — return unused tablets to your pharmacy

If you're managing a range of health conditions alongside allergies, our travel health range includes additional products for nausea and motion sickness that may complement your needs.

Written and reviewed by our qualified team

Your safety and success are our highest priorities. Our medical team rigorously evaluates every product and piece of advice we provide, ensuring you receive only the most effective, science-backed solutions available.

Frequently Asked Questions

Where can I buy Phenergan 25mg tablets online in the UK?

You can buy Phenergan 25mg tablets online from Cured Pharmacy, a UK GPhC-registered online pharmacy. No prescription is required as this is an over-the-counter pharmacy (P) medicine. Simply add to your basket and complete a short health check at checkout to confirm suitability.

How does Phenergan 25mg work in the body?

Phenergan contains promethazine hydrochloride, which blocks H1 histamine receptors throughout the body. This reduces the allergic response — sneezing, itching, runny nose — triggered when your immune system encounters an allergen. Because promethazine also crosses the blood-brain barrier, it produces a sedative effect that makes it useful for short-term sleep difficulties and nausea.

How do I take Phenergan 25mg tablets step by step?

Swallow the tablet whole with a glass of water — you can take it with or without food. For allergy relief, take 25mg at night or a lower dose (if using 10mg tablets) two to three times daily. For sleep, take one 25mg tablet 20–30 minutes before bedtime, and never exceed the stated dose.

What is the correct dose of Phenergan 25mg for adults?

For allergic conditions, the standard adult dose is 25mg at night, or 10mg two to three times daily if using a lower-strength preparation. For short-term insomnia, 25mg is taken once at bedtime. For travel sickness, 25mg is taken the night before travel and again on the morning of departure — always follow the patient information leaflet.

What is the best time to take Phenergan 25mg?

The best time depends on why you're taking it. For sleep, take it 20–30 minutes before you go to bed. For allergy symptoms, a single dose at night is often preferred to minimise daytime drowsiness. For travel sickness, timing is linked to your departure — take it the evening before and again on the morning of travel.

Can I take Phenergan 25mg for hay fever?

Yes, Phenergan 25mg tablets are licensed for hay fever and allergic rhinitis. They relieve sneezing, itchy eyes, and a runny nose by blocking histamine receptors. Bear in mind that promethazine is a sedating antihistamine, so if you need to stay alert during the day, a non-drowsy alternative from our allergy and hay fever range may be more suitable.

What are the side effects of Phenergan 25mg and how do I manage them?

The most common side effect is drowsiness, which is expected — avoid driving or operating machinery after taking this medicine. Dry mouth, blurred vision, and dizziness can also occur. Staying well hydrated and taking the tablet with food can help ease mild stomach discomfort; if side effects are troublesome, speak to your pharmacist.

Is Phenergan 25mg safe for children?

Phenergan 25mg tablets are not recommended for children under 5 years of age. For children aged 5 and over, lower doses are used and should be guided by a pharmacist or GP. Children can sometimes experience paradoxical excitability (restlessness rather than sedation), so always seek professional advice before giving this medicine to a child.

Who is eligible to take Phenergan 25mg tablets?

Phenergan 25mg is suitable for adults and children aged 5 and over who need relief from allergy symptoms, short-term insomnia, or nausea. It is not suitable for people with certain conditions including glaucoma, an enlarged prostate, epilepsy, or severe liver disease. Always complete the health check at checkout or speak to a pharmacist if you're unsure.

What happens if I miss a dose of Phenergan 25mg?

If you miss a dose, simply skip it and take your next dose at the usual time. Do not take a double dose to make up for a missed one. Because Phenergan is typically used on an as-needed basis rather than a strict schedule, missing a single dose is unlikely to cause any problems.

Can I drink alcohol while taking Phenergan 25mg?

No — you should avoid alcohol while taking Phenergan 25mg tablets. Alcohol significantly increases the sedative effect of promethazine, which can impair your judgement, coordination, and reaction times to a dangerous degree. This combination can also increase the risk of falls, particularly in older adults.

What are alternatives to Phenergan 25mg tablets?

Non-sedating second-generation antihistamines such as cetirizine or loratadine are widely used alternatives for daytime allergy relief. For sleep, other short-term options are available — browse our sleep aid range for alternatives. If nausea is your main concern, other antiemetics may also be appropriate — speak to your pharmacist.

How long can you take Phenergan 25mg for?

For short-term insomnia, Phenergan 25mg should not be used for more than 7 consecutive nights without medical advice, as tolerance can develop. For allergy symptoms, it can be used during periods of exposure, but long-term daily use should be discussed with your GP or pharmacist. It is not intended as a permanent solution for chronic conditions.

Can I take Phenergan 25mg during pregnancy or breastfeeding?

You should not take Phenergan 25mg tablets during pregnancy or while breastfeeding without first speaking to your GP or midwife. Promethazine can pass into breast milk and may cause sedation in a nursing infant. Your doctor can advise on the safest option for managing allergy or sleep symptoms during this time.

What does the latest research say about promethazine for sleep?

Current NHS guidance acknowledges promethazine as a short-term option for insomnia, though it notes that tolerance to its sedative effects can develop quickly — sometimes within a few days of regular use. Clinical guidance generally favours sleep hygiene and cognitive behavioural therapy for insomnia (CBT-I) as first-line approaches for longer-term sleep difficulties. Promethazine remains a useful short-term bridge when non-pharmacological measures haven't yet taken effect.

How Should You Take Phenergan 25mg Tablets?

Take Phenergan 25mg tablets by mouth, swallowing each tablet whole with a full glass of water. You can take them with or without food, though taking them with a light meal or snack may help if you find they cause any stomach discomfort. Never crush or chew the tablets.

What Is the Correct Dose of Phenergan 25mg?

The dose varies depending on your age and the condition being treated. Always refer to the patient information leaflet included in the pack, and never exceed the maximum stated dose. If you are unsure, ask your pharmacist before taking.

When Is the Best Time to Take Phenergan 25mg?

Timing matters with Phenergan because of its sedative effect. For allergy symptoms, taking your dose in the evening minimises the impact of drowsiness on your daily activities. For insomnia, take it 20–30 minutes before you plan to sleep to allow the medicine time to take effect. If you're using it for travel sickness, plan ahead — take the first dose the night before your journey.

How Long Can You Take Phenergan 25mg For?

Phenergan 25mg is intended for short-term use. For insomnia, do not use it for more than 7 consecutive nights without speaking to your GP, as tolerance to the sedative effect can develop. For allergy symptoms, it can be used during periods of allergen exposure, but if you find yourself needing it regularly over a long period, speak to your GP about longer-term allergy management options.

What Should You Do If You Miss a Dose of Phenergan 25mg?

If you miss a dose, skip it and take your next dose at the usual time. Do not take two doses together to compensate for a missed one. Because Phenergan is often taken on an as-needed basis, missing a single dose is unlikely to cause any issues — just continue as normal.

Do not exceed the recommended dose. If in doubt, speak to your pharmacist.

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Good price, good service

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Very prompt delivery and easy to order items if I can’t get out to the shop to purchase them….

Will most definitely will be ordering from you again….

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Kath Green

Easy to order medication.a d negotiate website. Order delivered promptly

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Anonymous

Really helped me as I have PTSD and difficulty sleeping after a critical illness. Despatch was quick too

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Good in time service Prompt n Reliable

What Are the Most Common Side Effects of Phenergan 25mg?

The most frequently reported side effect of Phenergan 25mg tablets is drowsiness. This is a direct result of promethazine crossing the blood-brain barrier and is, in some cases, the intended therapeutic effect. However, it can be problematic if you need to stay alert during the day.

  • Drowsiness and sedation
  • Dry mouth
  • Dizziness or light-headedness
  • Blurred vision
  • Headache

What Are the Less Common Side Effects of Phenergan 25mg?

Some people experience less common side effects, particularly with higher doses or prolonged use. Elderly patients and young children may be more susceptible to certain effects such as confusion or paradoxical excitability.

  • Restlessness or agitation (paradoxical excitability, more common in children)
  • Confusion or disorientation, particularly in older adults
  • Difficulty passing urine (urinary retention)
  • Constipation
  • Skin sensitivity to sunlight (photosensitivity)
  • Nausea or stomach discomfort
  • Palpitations or irregular heartbeat

What Are the Serious Side Effects of Phenergan 25mg?

Serious side effects are rare but require immediate medical attention if they occur. Stop taking Phenergan and seek urgent help if you notice any of the following:

  • Signs of a severe allergic reaction: skin rash, swelling of the face, lips, tongue, or throat, difficulty breathing
  • Unusual involuntary movements or muscle stiffness (extrapyramidal effects)
  • Severe confusion or hallucinations
  • Jaundice (yellowing of the skin or whites of the eyes) — may indicate liver problems
  • Significant drop in blood pressure causing fainting

What Should You Do If You Experience Side Effects?

For mild side effects such as dry mouth or drowsiness, these often improve as your body adjusts. Staying well hydrated, avoiding alcohol, and taking the tablet in the evening can help manage these effects. Do not drive or operate machinery if you feel drowsy after taking Phenergan.

If side effects are persistent, worsening, or causing you concern, stop taking the medicine and speak to your pharmacist or GP. You can also report side effects directly to the MHRA via the Yellow Card scheme at yellowcard.mhra.gov.uk.

Can Phenergan 25mg Interact With Other Medicines?

Yes — promethazine has several clinically significant interactions. The most important is with alcohol and other central nervous system (CNS) depressants, which can dangerously increase sedation. Always tell your pharmacist about all medicines you are currently taking, including over-the-counter products and herbal remedies.

  • Alcohol — significantly increases sedation
  • MAOIs (monoamine oxidase inhibitors) — serious interaction; do not combine
  • Other sedatives, sleeping tablets, or opioid painkillers — additive sedation
  • Anticholinergic medicines (e.g. for bladder problems or stomach cramps) — increased anticholinergic effects
  • Some antidepressants and antipsychotics — increased risk of side effects
  • Certain anticonvulsants — may affect seizure threshold

If you are concerned about any side effects, contact your pharmacist or GP immediately.

Patient Information Leaflet

Important - Before taking any medication, it is always important to read the Patient Information Leaflet (PIL)

View Patient Information Leaflet (PDF)

Written and reviewed by our qualified team

GPhC Number: 2233073
Tarun Kumar

Reviewed by:

Tarun Kumar

Superintendent/ Clinical Lead

📖 Find out more about our team of medical content authors and how we ensure the accuracy of our content with our content guidelines.

Content last updated: 31 Mar 2025

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