Decongestants are a type of medicine that can provide short-term relief for a blocked or stuffy nose (nasal congestion).
They work by reducing the swelling of the blood vessels in your nose, which helps open up the airways.
Types of decongestants
Decongestants are available as:
- nasal sprays
- tablets or capsules
- liquids or syrups
- flavoured powders to dissolve in hot water
Some products may just contain decongestant medication, but many are sold as "all-in-one" remedies that contain decongestants, painkillers or antihistamines.
Most decongestants can be bought over the counter from pharmacies without a prescription.
Who can take decongestants
Most people can use decongestants safely, but they're not suitable for everyone.
They should not be used by the following groups of people without getting advice from a pharmacist or GP first:
- babies and children – decongestants should not be given to children under 6, and should be used by children aged 6 to 12 for no longer than 5 days (ask a pharmacist for advice about this)
- pregnant and breastfeeding women – it's not clear whether it's safe to take decongestants if you're pregnant or breastfeeding, so you should only use them if advised to by a healthcare professional
- people taking other medications
- people with diabetes
- people with high blood pressure
- people with an overactive thyroid gland (hyperthyroidism)
- men with an enlarged prostate
- people with liver, kidney, heart or circulation problems
- people with glaucoma (increased pressure in the eye)
The patient information leaflet that comes with your medicine will state who should not use it and who should seek advice before using it.
How to use decongestants
Most decongestants should only be used between 1 and 4 times a day.
Check the patient information leaflet that comes with your medicine for advice about how much to take and how often to take it.
If you're unsure, ask a pharmacist for advice.
Decongestant nasal sprays and drops should not be used for more than a week at a time because using them for too long can make your stuffiness worse.
Speak to your GP if your symptoms fail to improve after this time.
Side effects of decongestants
Decongestant medicines do not usually have side effects, and any side effects you may experience are usually mild.
Possible side effects can include:
- feeling sleepy (look for non-drowsy medicines)
- irritation of the lining of your nose
- feeling or being sick
- a dry mouth
- feeling restless or agitated
- a rash
These side effects should pass after you stop taking the medication.
Interactions with other medications
Seek advice from a pharmacist or GP before taking decongestants if you're taking other medications.
Decongestants can increase or decrease the effect of some other medications.
For example, taking decongestants alongside some antidepressants can cause a dangerous rise in blood pressure.
It's also important to be wary of taking other medications if you're using an "all-in-one" decongestant remedy.
These products contain additional painkillers or antihistamines, so it could be dangerous to take extra doses of these medicines at the same time.
Page last reviewed: 28/02/2019
Next review due: 28/02/2022