Antihistamine
Cetirizine
Tablet or syrup
Quick Summary
Cetirizine blocks histamine, reducing sneezing, runny nose, itching and hives. It causes less drowsiness than older antihistamines.
Allergic rhinitis
Hives
Itchy skin
Medical Uses
Allergic rhinitis: Sneezing and runny nose.
Hives: Itchy rashes.
Itchy skin: From allergies and bites.
How it's taken
Usually taken once a day.
Your doctor decides the right dose for you and how long to take it.
Your doctor decides the right dose for you. Follow their instructions and the label.
Common Side Effects
Drowsiness
In some people.
Dry mouth
Sometimes.
Headache
Sometimes.
Interactions
Alcohol and sedatives
Increase drowsiness.
Critical Warnings
Drowsiness
Don't drive if it makes you sleepy.
Kidney problems
Dose may need adjusting.
Sources and further reading
Last updated 21 October 2026. For more detail, see these trusted health organisations.
- Cetirizine: drug information(opens in a new tab) · MedlinePlus, US National Library of Medicine
- Cetirizine: antihistamine that relieves allergy symptoms(opens in a new tab) · NHS