timothy grass pollen allergen at a glance
Medicine class
Grass pollen allergen immunotherapy
Licensed use
Grass pollen-induced allergic rhinitis and conjunctivitis in adults and children aged 5 years or older with confirmed sensitisation
Form
A fragile, rapidly dispersing lyophilisate placed under the tongue
Starting treatment
The first administration is taken under medical supervision because allergic reactions can occur
What is timothy grass pollen allergen used for?
Its selected UK licence covers disease-modifying treatment of:
Grass pollen-induced allergic rhinitis, with symptoms such as sneezing, nasal itching, blockage or a runny nose
Grass pollen-induced allergic conjunctivitis, with itchy, red, gritty or watery eyes
Use requires clinically relevant symptoms confirmed by skin-prick testing and/or grass pollen-specific IgE testing
How does timothy grass pollen allergen work?
Exposure through the lining beneath the tongue changes the immune response so that later grass pollen exposure causes less allergic inflammation. The complete mechanism is not established; observed changes include immune-regulatory responses and increased grass-specific IgG4 antibodies.
How to take timothy grass pollen allergen
Follow the allergy specialist's instructions. The first administration should occur under medical supervision.
Use dry fingers to remove the fragile lyophilisate from its blister.
Place it under the tongue immediately and allow it to disperse.
Avoid swallowing while it disperses and avoid eating or drinking immediately afterwards.
Seek advice before restarting after oral surgery, dental extraction or significant mouth inflammation.
timothy grass pollen allergen side effects
Common or expected effects
- Itching or tingling in the mouth or ears
- Mouth or lip swelling
- Throat irritation
- Sneezing, cough or runny nose
- Eye itching or swelling
- Abdominal pain, nausea, vomiting or diarrhoea
- Rash, itching or hives
- Tiredness or chest discomfort
Get urgent medical advice
- Anaphylaxis or another systemic allergic reaction
- Rapid swelling of the face, mouth or throat
- Difficulty breathing or swallowing, throat fullness or voice change
- Sudden worsening of asthma
- Persistent heartburn or swallowing problems, which require assessment for possible eosinophilic oesophagitis
timothy grass pollen allergen in pregnancy
Treatment should not be started during pregnancy because clinical experience is lacking. If pregnancy occurs after treatment has begun, continuation requires prescriber assessment; closer supervision is advised when asthma is present.
timothy grass pollen allergen while breastfeeding
Clinical breastfeeding data are unavailable, although effects on a breastfed infant are not anticipated. Discuss starting or continuing treatment with the prescriber.
timothy grass pollen allergen interactions
Formal human interaction studies have not been conducted. Important considerations include:
Antihistamines, corticosteroids and mast-cell stabilisers
These may increase tolerance of local reactions; their use should be reviewed rather than stopped without advice.
Beta-blockers, tricyclic antidepressants, monoamine oxidase inhibitors and COMT inhibitors
These may complicate the use or tolerability of adrenaline if anaphylaxis occurs, so treatment should be reviewed before initiation.
Other allergen immunotherapy
Evidence about simultaneous treatment with other allergens is limited and specialist assessment is required.
Common questions about timothy grass pollen allergen
Answers are fully visible for fast scanning and source review.
Is timothy grass pollen allergen the same as an antihistamine?
No. Antihistamines temporarily suppress allergy symptoms, whereas timothy grass pollen allergen is immunotherapy intended to modify the immune response to grass pollen.
Does timothy grass pollen allergen require an allergy test first?
Yes. Its UK licence requires clinically relevant symptoms plus a positive grass pollen skin-prick and/or specific IgE test.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.