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GRASTEK is a prescription medicine used for sublingual (under the tongue) immunotherapy to treat Timothy and related grass pollen allergies that can cause sneezing, runny or itchy nose, stuffy or congested nose, or itchy and watery eyes. GRASTEK may be prescribed for persons 5 through 65 years of age who are allergic to grass pollen.

GRASTEK is taken for about 12 weeks before the grass pollen season and throughout grass pollen season. GRASTEK may also be taken daily for 3 years to provide a sustained effect for a fourth year in which you do not have to take GRASTEK.

GRASTEK is NOT a medication that gives immediate relief for symptoms of grass allergy.

free support program for people with grass allergies

Important Safety Information about GRASTEK (continued)

Important Safety Information about GRASTEK 

  • GRASTEK can cause severe allergic reactions that may be life-threatening. Stop taking GRASTEK and get medical treatment right away if you or your child has any of the following symptoms after taking GRASTEK:

    • Trouble breathing
    • Throat tightness or swelling
    • Trouble swallowing or speaking
    • Dizziness or fainting
    • Rapid or weak heartbeat
    • Severe stomach cramps or pain, vomiting, or diarrhea
    • Severe flushing or itching of the skin
  • Do not take GRASTEK if you or your child has severe, unstable or uncontrolled asthma; had a severe allergic reaction in the past that included trouble breathing, dizziness or fainting, or rapid or weak heartbeat; had difficulty with breathing due to swelling of the throat or upper airway after using any sublingual immunotherapy before; has ever been diagnosed with eosinophilic esophagitis; or is allergic to any of the inactive ingredients contained in GRASTEK.
  • For home administration of GRASTEK, your doctor will prescribe auto-injectable epinephrine, a medicine you can inject if you or your child has a severe allergic reaction after taking GRASTEK. Talk to your doctor or read the epinephrine patient information if you have any questions about the use of auto-injectable epinephrine.
  • The first dose of GRASTEK must be taken in the doctor’s office. After taking the first tablet, you or your child will be watched for at least 30 minutes for symptoms of a serious allergic reaction.

Important Safety Information about GRASTEK® (Timothy Grass Pollen Allergen Extract). (continued below)


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Important Safety Information about GRASTEK


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