Nasal decongestants are medicines that help relieve a blocked or stuffy nose and sinus congestion by reducing swelling of the blood vessels inside the nasal passages.
This helps improve airflow, making it easier to breathe through your nose and allowing mucus to drain more easily.
Nasal congestion can be caused by lots of different things as it’s a symptom of a cold, allergies, and flu. Over-the-counter decongestants can be bought without a prescription to help relieve nasal congestion, so you can breathe easier.
What are nasal decongestants and how do they work?
Congestion is part of your body’s natural response to an allergen, infection or illness. Blood vessels in the nose swell, causing a blocked or stuffy feeling.
Decongestants work by reducing swelling in the blood vessels inside the nose.
This helps:
Open the nasal passages
Allow mucus to drain more easily
Improve airflow
Make it easier to breathe through your nose
Decongestants do not treat the underlying cause of congestion, but they can provide temporary relief from symptoms.
What ingredients are used in decongestants?
Decongestants contain active ingredients that help reduce swelling in the nasal passages.
These ingredients vary depending on the product type (tablet, capsule, liquid or nasal spray). There are three main active ingredients used across the SUDAFED® range:
Pseudoephedrine – A decongestant available in tablets or in a liquid. It helps relieve nasal congestion by narrowing swollen blood vessels.
Phenylephrine – A decongestant available in capsules that helps reduce nasal congestion.
Xylometazoline – A decongestant found in nasal sprays that helps reduce swelling in the nasal passages.
Some Sudafed® products also include additional ingredients to help relieve other cold and flu symptoms:
Caffeine – Helps reduce tiredness
Guaifenesin – Helps thin and loosen mucus so it is easier to cough up
Ibuprofen – Helps relieve pain and reduce inflammation
Paracetamol – Helps relieve headaches, fever and mild to moderate pain
Always read the label and do not take more than one decongestant at the same time. If you are unsure, speak to a pharmacist.
What causes nasal congestion?
Nasal congestion can be caused by a range of conditions, including:
Allergy - Your immune system can react to allergens such as dust, mould, pet dander or pollen. This leads to inflammation inside the nose, which can cause congestion and make it difficult to breathe.
Flu - Flu is the results of a viral infection that can cause congestion alongside other symptoms such as body aches, headaches, sore throat, cough and tiredness. Symptoms often occur together, which is why some Sudafed products have multiple active ingredients to help relieve congestion and other symptoms of flu at the same time.
Head cold - A head or common cold affects the nose and sinuses, often causing congestion. Cold symptoms may develop more gradually than flu symptoms, but can still make breathing through your nose uncomfortable.
Sinus - Sinus infections (sinusitis) occur when the sinuses become blocked and mucus cannot drain properly. This can lead to congestion, pressure around the nose, forehead and cheekbones, and sometimes headaches.
In these instances, congestion is caused by swelling in the nasal passages, which restricts airflow and makes breathing through the nose more difficult.
What types of decongestants are available?
Decongestants are available in different formats in the Sudafed range depending on your preference:
Tablets
Tablets containing pseudoephedrine help reduce swelling in the nasal passages, making it easier to breathe through your nose.
Capsules
Capsules containing phenylephrine helps reduce nasal congestion by decreasing swelling in the nasal passages
Nasal sprays
Nasal sprays containing xylometazoline acts fast, and help to reduce swelling and relieve congestion.
Liquid
Liquid containing pseudoephedrine helps reduce nasal swelling to relieve congestion.
How long do decongestants take to work?
The time it takes for decongestants to work depends on the product used.
Sudafed products containing pseudoephedrine, found in liquid and tablet formulations, works in 30 minutes on nasal congestion
Nasal sprays containing xylometazoline (Sudafed Blocked Nose Spray and Sudafed Sinus-Ease) gets to work in minutes. Sudafed Plus Nasal spray gets to work from 5 minutes.
Always read the label and do not take more than one decongestant at the same time. If you are unsure, speak to a pharmacist.
How long should I use nasal decongestants?
Nasal decongestants are designed for short-term use to help relieve congestion.
Recent guidance from the MHRA recommends that nasal sprays containing xylometazoline should be used for no more than five consecutive days.
This helps:
Ensure the product is used as intended for short-term relief
Reduce the risk of side effects linked to prolonged or repeated use
Encourage seeking medical advice if symptoms do not improve
SUDAFED® nasal sprays containing xylometazoline are intended for short-term use only and prolonged use may lead to worsening nasal congestion.
If your symptoms persist, worsen or do not improve after five days, you should stop using the product and speak to a pharmacist or doctor for advice.
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