Overview
Grazax hay fever treatment
Grazax® is a medicine used to treat hay fever caused by grass pollen. It’s a tablet that you need to take every day for 3 years.
Grazax helps your body get used to grass pollen so you get fewer allergy symptoms.
If you’re allergic to grass pollen, you might get:
- an itchy or runny nose, or sneezing caused by inflammation of the nose (allergic rhinitis)
- red, itchy, irritated eyes caused by inflammation of the eye (allergic conjunctivitis)
You can usually treat hay fever with other medicines like:
- antihistamine tablets
- combination nasal sprays that contain an antihistamine and a steroid
- eye drops
If these medicines do not work and your allergy is affecting your quality of life, we might recommend Grazax.
Important
Read the leaflet inside your Grazax medicine package for more information.
How Grazax treatment works
Grazax contains a small, fixed amount of grass pollen extract. This is the substance that causes your allergic reaction (allergen).
Taking small doses of the allergen each day helps your body get used to it. Your immune system will slowly build up a tolerance to grass pollen. This means your body will react less to grass pollen and you will get fewer symptoms.
This type of treatment is called desensitisation or immunotherapy.
You’ll need to continue taking your regular hay fever medicines while taking Grazax. Within 3 years, your symptoms should improve. After that, you should be able to reduce the amount of other hay fever medicines you take.
Who can have Grazax treatment
Before you start treatment, your healthcare team will do an assessment to check if Grazax is a safe treatment option for you.
We’ll also ask you to complete a questionnaire about your grass pollen allergy and how it affects your quality of life.
Tell us if:
- you have any other health conditions
- you take any medicines – including medicines you buy from a pharmacy or shop, such as vitamins, supplements and herbal or alternative medicines
- you’re pregnant or might be pregnant
- you’re breastfeeding
- you have a severe fish allergy – this is important because Grazax contains fish gelatine
- you have previously had a severe allergic reaction to other allergen immunotherapy injections
Do not take Grazax if:
- you have a condition that affects your immune system
- you have cancer
- you have severe mouth sores and inflammation
- you have asthma that’s difficult to control
Read the leaflet inside your medicine package for a full list of health conditions that might affect how your body responds to Grazax treatment.
Resource number: 2344/VER4
Last reviewed: March 2026
Next review due: March 2029
