Decongestants are medicines that are used to help reduce the symptoms of a blocked or stuffy nose. They may be helpful for congestion caused by various conditions. Most commonly, decongestants are used for a cold, sinusitis, hay fever, allergies and rhinitis. These medicines are available as nose drops or nasal sprays and also as tablets, capsules and syrup. Decongestant nose drops or nasal sprays should not be used for more than five days at a time.
These medicines are not suitable for children under 6 years old.
What are decongestants?
Decongestants are medicines that are used to help ease a blocked or stuffy nose (nasal congestion). Conditions which cause congestion include:
These conditions cause swelling of the tissues and blood vessels that line the nasal passageway and sinuses. This, in turn, causes the nose to become blocked.
A number of decongestants are available in the UK. They include:
Dr Krishna Vakharia, 21st February 2024
A note on pseudoephedrine-containing products.
The Medicines and Healthcare products Regulatory Agency has issued a caution for those using pseudoephedrine-containing products.
There have been rare reports of two conditions associated with pseudoephedrine use - posterior reversible encephalopathy syndrome (PRES) and reversible cerebral vasoconstriction syndrome (RCVS).
Following a review by MHRA - the safety information of all pseudoephedrine-containing medicines will be updated to provide clearer descriptions of these risks and potential risk factors for these conditions for both patients and healthcare professionals.
PRES- also known as reversible posterior leukoencephalopathy syndrome (RPLS). This is a rare condition in which parts of the brain are affected by swelling - usually as a result of an underlying cause. Symptoms include headache, changes in vision, and seizures, with some developing other neurological symptoms such as confusion or weakness of one or more limbs. Most patients fully recover.
RCVS - is a neurological disorder. There is a sudden onset of severe headache associated with narrowing of the blood vessels that supply blood to the brain. On brain imaging the narrowing of the blood vessels can look similar to a “string of beads”. Very rarely, RCVS can present as a medical emergency with strokes (ischaemic strokes or bleed), seizure or as brain swelling. Usually, the narrowing resolves by itself within three months, and most patients fully recover.
- Pseudoephedrine is for short term use only and should only be used to relieve symptoms of nasal and sinus congestion in colds, flu, and allergies.
- No one should take pseudoephedrine if they have high blood pressure (hypertension) or hypertension not controlled by their medicines, or if they have severe acute (sudden onset) or chronic (long-term) kidney disease or kidney failure.
- If you experience a severe headache that develops very quickly or you suddenly feel sick or are vomiting, confused or experiencing seizures or changes in vision while taking this medicine, stop taking it immediately and seek urgent medical attention.
Some are available as nasal sprays or drops (sometimes referred to as topical decongestants). Some are available to take by mouth as a tablet or syrup. Some are available in both forms.
These medicines come in various brand names. Many are available to buy over the counter from your pharmacy. They may also be available as a combined tablet that contains a decongestant and a painkiller such as paracetamol.
There are a number of other options that are sometimes used to treat nasal congestion. For example, the following may be helpful:
- Salt water (saline) nose drops. These are a popular treatment for a stuffy nose in a baby.
- Steam inhalations. Steam may help to clear the nasal congestion but only has an effect for a short time. This may be useful before bedtime to help you get off to sleep.
How do decongestants work?
Most decongestants work by reducing the swelling of the blood vessels in your nose, throat and sinuses. As it is this swelling causing the congestion, the medication improves the blocked-up feeling.
Ipratropium nasal spray works slightly differently by drying up the secretions of the nose.
Decongestant nasal sprays tend to have an immediate effect to clear a blocked nose. Oral tablets and capsules may take a little longer to work because they need to be absorbed into the body from the gut.
Are you eligible for a free NHS flu vaccination?
You may be entitled to a free NHS flu vaccination from your GP or local pharmacist. Find out if you are eligible today.
When are decongestants used or prescribed?
If you have hay fever, they are helpful to use for a few days to clear a blocked nose when you first use a steroid nasal spray. The steroid can then get to the lining of the nose more effectively. If you have acute sinusitis, decongestants can relieve symptoms whilst you are waiting for your immune system to clear the infection. However, they are not thought to shorten the duration of sinusitis.
Decongestant nasal sprays and nose drops should only be used for about 3-5 days at a time. If they are used for longer than this a rebound, more severe congestion of the nose often develops. Oxymetazoline and xylometazoline nasal preparations are thought to be more likely to cause rebound nasal congestion because they are the strongest.
Oral decongestants are not thought to cause this problem when they are stopped. Decongestant sprays and drops are thought to work better than oral tablets or capsules.
Some important considerations
Some important considerations about decongestants relate to:
- Children under 6 years old.
- Taking other medicines.
Children under 6 years old
These medicines should not be used in children under 6 years old. The risk of side-effects is higher than any benefit they may have. Children aged 6 to 12 can use some decongestants following discussion with a pharmacist.
Taking other medicines
This is important if you are already taking paracetamol or ibuprofen to help the symptoms of your infection (for example, a high temperature). You may take too much paracetamol or ibuprofen (overdose) without realising. Taking too much paracetamol can damage your liver.
You should also not use these decongestants while you are taking a certain type of antidepressant called a monoamine-oxidase inhibitor (MAOI) and for two weeks after you stop it. This is because, when taken at the same time as an MAOI antidepressant, decongestants may cause very large increases in blood pressure.
Side-effects of decongestants
Most people are able to take or use decongestant medicine with very few, or no, side-effects. If side-effects do occur, they usually go away after a few days. Some nasal decongestants may produce side-effects such as:
Oral decongestants may cause side-effects such as:
- Problems with sleeping.
- Being aware of a fast or fluttering heartbeat.
See the leaflet that came with your medicines for more detailed information on the side-effects of these medicines.
Can I buy decongestants?
There are a large number of oral and nasal decongestants that you can buy from your local pharmacy or supermarket. They have many different brand names.
Who cannot take decongestants?
Some people should avoid taking decongestants. This includes people who have:
- Heart problems, such as coronary artery disease, heart failure or arrhythmias (irregular heart beat).
- High blood pressure.
- Kidney problems, such as chronic kidney disease.
- An overactive thyroid gland.
- Prostate problems, such as difficulty passing urine due to prostate enlargement.
- Depression and take an MAOI antidepressant.
- Circulation problems, including Raynaud’s phenomenon.
See the leaflet that came with your medicines for more detailed information on who should avoid taking these medicines. If you are unsure whether these medicines are safe for you, always ask your pharmacist or doctor for advice.
How to use the Yellow Card Scheme
If you think you have had a side-effect to one of your medicines you can report this on the Yellow Card Scheme. You can do this online at www.mhra.gov.uk/yellowcard.
The Yellow Card Scheme is used to make pharmacists, doctors and nurses aware of any new side-effects that medicines or any other healthcare products may have caused. If you wish to report a side-effect, you will need to provide basic information about:
- The side-effect.
- The name of the medicine which you think caused it.
- The person who had the side-effect.
- Your contact details as the reporter of the side-effect.
It is helpful if you have your medication - and/or the leaflet that came with it - with you while you fill out the report.
Further reading and references
British National Formulary (BNF); NICE Evidence Services (UK access only)
Over-the-counter cough and cold medicines for children; Medicines and Healthcare products Regulatory Agency (MHRA), 2014
Sinusitis; NICE CKS, March 2021 (UK access only)
Common cold; NICE CKS, February 2022 (UK access only)
Deckx L, De Sutter AI, Guo L, et al; Nasal decongestants in monotherapy for the common cold. Cochrane Database Syst Rev. 2016 Oct 1710(10):CD009612. doi: 10.1002/14651858.CD009612.pub2.
De Sutter AI, Eriksson L, van Driel ML; Oral antihistamine-decongestant-analgesic combinations for the common cold. Cochrane Database Syst Rev. 2022 Jan 211(1):CD004976. doi: 10.1002/14651858.CD004976.pub4.
Watts AM, Cripps AW, West NP, et al; Modulation of Allergic Inflammation in the Nasal Mucosa of Allergic Rhinitis Sufferers With Topical Pharmaceutical Agents. Front Pharmacol. 2019 Mar 2910:294. doi: 10.3389/fphar.2019.00294. eCollection 2019.
Update on MHRA safety review of medicines containing pseudoephedrine; Medicines & Healthcare products Regulatory Agency, GOV.UK (February 2024)