Sominex 20mg – 8 Tablets

Description

Sominex 20mg – 8 Tablets

Sominex 20mg tablets are a short-term sleep aid used to help relieve occasional sleeplessness in adults. They contain promethazine hydrochloride, an antihistamine with sedative properties that helps you fall asleep more easily.

⸻

How It Works

Promethazine hydrochloride works by blocking histamine receptors in the brain, which produces a calming, drowsy effect. This helps reduce the time it takes to fall asleep and can improve the quality of your rest when taken before bedtime.

⸻

Directions for Use

Adults aged 16 and over: take 1 tablet (20mg) approximately 20 minutes before bedtime. Do not exceed 1 tablet in 24 hours. Sominex is not suitable for children under 16 years of age. This medicine should only be used for short-term relief of occasional sleeplessness — do not take for more than 7 consecutive nights without speaking to a doctor. Always read the patient information leaflet before use. If you are unsure about the correct dose, speak to your PillSorted pharmacist.

⸻

Active Ingredients

• Promethazine hydrochloride 20mg per tablet

⸻

Possible Side Effects

• Drowsiness or sedation the next day
• Dizziness or difficulty concentrating
• Dry mouth, nose, or throat
• Blurred vision
• Constipation or difficulty passing urine
• Restlessness or confusion (more common in older adults)
• Headache

If you experience any serious side effects, stop taking this medicine and seek medical advice immediately.

⸻

Who Should Not Take This Medicine

• Children under 16 years of age
• People who are allergic to promethazine hydrochloride or any other ingredient in the tablet
• People taking monoamine oxidase inhibitors (MAOIs) or who have taken them in the last 14 days
• People with certain conditions affecting the liver or kidneys — speak to your doctor first
• People with epilepsy, glaucoma, or an enlarged prostate
• People with breathing difficulties or sleep apnoea
• Elderly patients should use with caution due to increased risk of confusion and falls

⸻

Interactions

Sominex may interact with other medicines that cause drowsiness, including sleeping tablets, anxiety medicines, antidepressants, and strong painkillers, increasing the sedative effect. It may also interact with anticholinergic medicines (such as those used for bladder problems or travel sickness), and certain antidepressants including tricyclics and SSRIs. Avoid taking Sominex alongside other antihistamines. Tell your PillSorted pharmacist or doctor about all medicines you are currently taking, including herbal remedies and supplements.

⸻

Pregnancy and Breastfeeding

Sominex is not recommended during pregnancy or while breastfeeding, as promethazine hydrochloride can pass into breast milk and may affect a nursing baby. It may also cause complications in late pregnancy, particularly near the time of delivery. Speak to your doctor or PillSorted pharmacist before use if you are pregnant, trying to conceive, or breastfeeding.

⸻

Alcohol

Do not drink alcohol while taking Sominex. Alcohol significantly increases the sedative effect of promethazine, which can lead to excessive drowsiness, impaired judgement, and an increased risk of accidents. Avoid alcohol on any day you take this medicine.

⸻

Driving and Operating Machinery

Sominex causes drowsiness and may impair your concentration, reaction times, and ability to drive or operate heavy machinery — both the night you take it and the following morning. Do not drive or operate machinery until you know how this medicine affects you. If you feel drowsy after taking Sominex, do not drive.

⸻

Storage

Store below 25°C in a dry place, away from direct sunlight and moisture. Keep out of sight and reach of children. Do not use after the expiry date shown on the packaging.

⸻

Important Information

• This product is a medicine. Speak to your doctor or PillSorted pharmacist before taking this product if you have an underlying medical condition or are taking any other medication or complementary therapy.
• If symptoms worsen or persist, contact your doctor.
• If pregnant, trying to conceive or breastfeeding, seek medical advice before use.
• If you suffer from allergies, confirm suitability with your PillSorted pharmacist before use.
• Store out of sight and reach of children.
• Read the enclosed patient information leaflet carefully before use.
• Contact your GP where appropriate.

⸻

Patient Information Leaflet

For the full Patient Information Leaflet (PIL) for this medicine, visit the electronic Medicines Compendium (EMC). For further information about this medicine, visit NHS.uk.

⸻

This content has been medically reviewed and approved by Zeinab Ardeshir (GPhC 2075730), Superintendent Pharmacist at PillSorted (GPhC-registered online pharmacy 9011258). Last reviewed: February 2026.

Brand	Sominex