Grazax (Phleum Pratense (225))

Grazax is a prescription sublingual tablet that contains 225 µg of the timothy grass allergen Phleum pratense. It is classified as an allergen immunotherapy product and is marketed in the European Union for the treatment of grass‑pollen‑induced allergic rhinitis. The tablet is placed under the tongue, where it delivers a controlled dose of allergen to promote immune tolerance. It is taken daily before the grass season to build tolerance.

Grazax is indicated for patients with seasonal allergic rhinitis or allergic rhinoconjunctivitis caused by timothy grass pollen, and it is prescribed as a disease‑modifying therapy.

- Pre‑seasonal treatment to reduce symptoms when grass pollen exposure begins. - Adjunct to standard antihistamine or intranasal corticosteroid therapy. - Long‑term immunotherapy aimed at modifying the underlying allergic response. - Suitable for adults and children aged 5 years and older with confirmed grass‑pollen allergy. - Can be used in patients who have experienced inadequate relief from conventional allergy medications.

Side effects of sublingual grass‑pollen immunotherapy are generally mild, but some reactions may require medical attention.

Common: - Mild oral itching or tingling at the site of tablet placement. - Transient sore throat or mild irritation of the mouth. - Nasal congestion or runny nose shortly after dosing. - Mild gastrointestinal discomfort such as nausea. - Mild headache or feeling of fatigue after the first few doses. - Temporary increase in eye itching or watery eyes.

Serious: - Anaphylaxis or severe systemic allergic reaction. - Swelling of the lips, tongue, or throat that impairs breathing. - Urticaria (hives) covering large areas of the body. - Bronchospasm or wheezing requiring emergency care.

Before starting Grazax, clinicians should evaluate patient history and consider specific safety considerations to minimize risk.

- Confirm a documented allergy to timothy grass pollen through skin testing or specific IgE measurement. - Avoid initiating therapy in patients with uncontrolled asthma or a history of severe allergic reactions. - Do not use in individuals taking beta‑blockers, as they may interfere with emergency treatment of anaphylaxis. - Pregnancy and breastfeeding status should be assessed, as safety data are limited. - Patients should be observed for at least 30 minutes after the first dose to monitor for systemic reactions. - Discontinue the tablet if signs of anaphylaxis, severe swelling, or bronchospasm develop.

Grazax may interact with other medications or substances that affect immune response or allergic reaction management.

Avoid: - Concurrent use of omalizumab or other biologic agents targeting IgE without specialist supervision. - Simultaneous administration of high‑dose systemic corticosteroids that could suppress the intended immunologic effect. - Live vaccines administered within two weeks of starting therapy, as immune modulation may affect vaccine response.

Use with caution: - Beta‑blockers, because they can reduce the effectiveness of epinephrine in treating anaphylaxis. - ACE inhibitors or ARBs, which may increase the risk of angio‑edema in susceptible individuals. - Antihistamines, which can mask early signs of an allergic reaction during dose escalation. - Non‑steroidal anti‑inflammatory drugs (NSAIDs) may exacerbate gastrointestinal irritation when combined with sublingual tablets.