A non-drowsy antihistamine
Desloratadine
A once-daily, less-sedating antihistamine for hay fever and hives; non-drowsy for most people, though some can still feel a little drowsy.
What is Desloratadine?
Desloratadine is a non-drowsy (less-sedating) antihistamine taken once a day for allergies such as hay fever and itchy skin rashes (hives or urticaria). It blocks histamine, the chemical released in allergic reactions, easing sneezing, a runny or itchy nose, itchy eyes and itching. It is less likely to make you sleepy than older antihistamines, although a few people still feel some drowsiness.
Education and reference only. This is a plain-language guide to Desloratadine — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Desloratadine is a non-drowsy (second-generation) antihistamine used in the UK for allergic conditions such as hay fever (allergic rhinitis) and itchy skin rashes including hives (urticaria). It relieves symptoms such as sneezing, a runny or itchy nose, itchy watery eyes and an itchy rash. It is the active form of loratadine, taken once a day, and is designed to be much less sedating than older antihistamines, though a minority of people still notice some drowsiness.
How it works
Desloratadine blocks histamine, the chemical released by the body during an allergic reaction. When you are exposed to something you are allergic to, histamine causes the sneezing, itching, runny nose and watery eyes of an allergy. By blocking histamine at its receptors, desloratadine reduces these symptoms. Like other non-drowsy antihistamines, it acts mainly outside the brain, which is why it is much less likely to cause drowsiness than older types.
What it treats
Conditions Desloratadine is used for
Practical use
How to take Desloratadine
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Take it once a day, at about the same time, with or without food.
- For hay fever, take it regularly through the pollen season rather than only on bad days for steadier control.
- Although it is non-drowsy, see how it affects you before driving or using machinery, as a few people still feel sleepy.
- Go easy on alcohol, which can add to any drowsiness.
- If you miss a dose, take it when you remember unless it is nearly time for the next one — do not double up.
Weighing it up
Advantages & disadvantages of Desloratadine
Advantages
- It is effective for hay fever and itchy allergic rashes such as hives.
- Once-daily dosing is simple and convenient.
- It is much less likely to cause drowsiness than older, sedating antihistamines.
Disadvantages
- Although non-drowsy, it can still cause some drowsiness in a minority of people.
- It may not fully control severe symptoms on its own, sometimes needing an added nasal spray or eye drops.
- It is used with caution in people with significant liver or kidney problems.
Practical use
Good to know
Desloratadine is usually taken once a day and gives steady cover, so it can be taken regularly rather than only when symptoms flare. Although it is a non-drowsy antihistamine, 'less sedating' is not the same as 'never sedating' — a minority of people do feel a little drowsy, so see how it affects you before driving or operating machinery, particularly at first. Alcohol can add to any drowsiness. For hay fever it often works best taken regularly through the pollen season. It is used with caution in people with significant liver or kidney problems.
Who should not take it / use with caution
- Anyone who has had a serious allergic reaction to desloratadine or to loratadine.
- Used with caution in people with significant liver or kidney problems.
- People should check first if they have a rare intolerance to certain sugars, which some formulations contain.
Monitoring
- Review of whether allergy symptoms are well controlled.
- Checking for any troublesome drowsiness, especially before driving or using machinery.
- Caution and review in people with significant liver or kidney problems.
Side effects
- Some drowsiness or tiredness in a minority of people.
- Dry mouth and headache.
- Occasionally, tummy upset such as nausea.
- Rarely, a faster heartbeat or, very rarely, an allergic reaction (seek advice).
Key interactions
- Alcohol and other sedating medicines can add to any drowsiness.
- It has relatively few important drug interactions compared with older antihistamines.
- Tell your prescriber and pharmacist about all your medicines, including anything bought over the counter.
Available as: Tablets and an oral solution.
Answers
Desloratadine: frequently asked questions
Does desloratadine make you drowsy?
It is a non-drowsy (less-sedating) antihistamine, so most people are not affected. However, a minority still feel a little drowsy — 'less sedating' is not the same as 'never sedating'. See how it affects you before driving or using machinery, especially at first.
How often do I take desloratadine?
It is usually taken once a day, at about the same time, with or without food. For hay fever, taking it regularly through the pollen season often gives better control than only taking it on bad days.
What is desloratadine used for?
It is used for allergic conditions such as hay fever (allergic rhinitis) and itchy skin rashes including hives (urticaria). It eases symptoms such as sneezing, a runny or itchy nose, itchy watery eyes and itching.
How is desloratadine different from loratadine?
Desloratadine is the active form that the body produces from loratadine. Both are non-drowsy once-daily antihistamines and work in a similar way; your prescriber or pharmacist can advise which is most suitable for you.
Can I drink alcohol with desloratadine?
Alcohol can add to any drowsiness, so it is best to be careful, particularly when you first start it or if you find it makes you sleepy. See how the medicine affects you before combining it with alcohol.
The wider class
About Antihistamines
Desloratadine belongs to the antihistamines class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
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Authoritative sources
- BNF
- NICE CKS
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