This medicine is available without prescription to treat minor conditions. However, you still need to take it carefully to get the best results from it.

• Keep this leaflet, you may need to read it again
• Ask your pharmacist if you need more information or advice

• If you are allergic to any of the ingredients (see "What is in this medicine")
• If you have heart or circulatory problems
• If you have high blood pressure or hypertension not controlled by your medication (including that due to a tumour near your kidney)
• If you have diabetes, glaucoma or an overactive thyroid
• If you have severe acute (sudden) or chronic (long-term) kidney disease or kidney failure
• If you are taking monoamine oxidase inhibitors (for depression) or have taken them within the last 14 days
• If you are taking other medicines containing pseudoephedrine, or other decongestants
• If you are a man with prostate problems
• If you are pregnant or breastfeeding

If you develop a feverish generalised erythema associated with pustules, stop taking this medicine and contact your doctor or seek medical attention immediately. See section 'Possible side effects'.

Sudden abdominal pain or rectal bleeding may occur with this medicine, due to inflammation of the colon (ischaemic colitis). If you develop these gastro-intestinal symptoms, stop taking this medicine and contact your doctor or seek medical attention immediately. See 'Possible side effects' section.

Reduction of blood flow to your optic nerve may occur with pseudoephedrine. If you develop sudden loss of vision, stop taking Boots Decongestant Tablets and contact your doctor or seek medical attention immediately. See ‘Possible side effects’ section.

Cases of posterior reversible encephalopathy syndrome (PRES) and reversible cerebral vasoconstriction syndrome (RCVS) have been reported following use of medicines containing pseudoephedrine. PRES and RCVS are rare conditions that can involve reduced blood supply to the brain. Stop using this medicine immediately and seek immediate medical assistance if you develop symptoms that may be signs of PRES or RCVS (see 'Possible side effects' for symptoms)

Information about some of the ingredients in this medicine

This medicine contains less than 1 mmol sodium (23 mg) per tablet, that is to say essentially 'sodium-free'.

Before you take these tablets, make sure that you tell your pharmacist about ANY other medicines you might be using at the same time, particularly the following:

• Digoxin (for heart problems)
• Tricyclic antidepressants
• Ergot alkaloids (for migraine)

If you are unsure about interactions with any other medicines, talk to your pharmacist. This includes medicines prescribed by your doctor and medicine you have bought for yourself, including herbal and homeopathic remedies.

• Difficulty in breathing, swelling of the face, neck, tongue or throat (severe allergic reactions)
• Sudden onset of fever, reddening of the skin, or many small pustules (possible symptoms of Acute Generalized Exanthematous Pustulosis - AGEP) may occur within the first 2 days of treatment with this medicine. See section ‘Before you take this medicine’.

Frequency not known:

Inflammation of the colon due to insufficient blood supply (ischaemic colitis).

Reduced blood flow to the optic nerve, loss of vision (Ischaemic optic neuropathy)

Serious conditions affecting blood vessels in the brain known as posterior reversible encephalopathy syndrome (PRES) and reversible cerebral vasoconstriction syndrome (RCVS)

Stop using this medicine immediately and seek urgent medical attention if you develop symptoms, that may be signs of posterior reversible encephalopathy syndrome (PRES) and reversible cerebral vasoconstriction syndrome (RCVS). These include:

• severe headache with a sudden onset
• feeling sick
• vomiting
• confusion
• seizures changes in vision

• Skin rash
• Feeling sick, being sick, headache, dry mouth
• Fast or irregular heartbeat, high blood pressure
• Restlessness, difficulty sleeping, tremors, anxiety
• Occasionally, difficulty in passing urine (in men)
• Rarely, hallucinations (particularly in children)

If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.

By reporting side effects you can help provide more information on the safety of this medicine.