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Grastek

Generic Name: timothy grass pollen allergen extract (TIM-oh-thee GRAS POL-uhn al-er-juhn EK-strakt)
Brand Name: Grastek

Grastek can cause severe and sometimes life-threatening allergic reactions. Do not take Grastek if you have severe or uncontrolled asthma. After you take the first dose of Grastek, your doctor will watch you closely for at least 30 minutes. Your doctor should give you another medicine (epinephrine) to use in case of an allergic reaction. Be sure you know how and when to use it. Tell your doctor if you are taking a beta-blocker (eg, metoprolol). Epinephrine may not work as well if you are taking a beta-blocker. Discuss any questions or concerns with your doctor.


Grastek is used for:

Treating allergies caused by Timothy grass pollen. It may also be used for other conditions as determined by your doctor.

Grastek is an allergen extract. Exactly how it works is not known.

Do NOT use Grastek if:

  • you are allergic to any ingredient in Grastek or to any other allergen immunotherapy medicines given under the tongue (sublingual)
  • you have severe or uncontrolled asthma
  • you have a history of any severe allergic reaction
  • you have a history of eosinophilic esophagitis

Contact your doctor or health care provider right away if any of these apply to you.

Before using Grastek:

Some medical conditions may interact with Grastek. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

  • if you are pregnant, planning to become pregnant, or are breast-feeding
  • if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • if you have allergies to medicines, foods, or other substances
  • if you have lung or breathing problems (eg, asthma, chronic obstructive pulmonary disease [COPD]), heart problems (eg, coronary artery disease, irregular heartbeat), high blood pressure, or mouth irritation (eg, mouth sores, ulcers, or cuts; mouth infection, thrush or white patches in the mouth or throat)
  • if you have had a recent heart attack
  • if you are getting other allergen treatment or you have recently had oral surgery or a tooth removed
  • if you are taking an alpha-blocker (eg, doxazosin), a beta-blocker (eg, metoprolol), chlorpheniramine, digoxin, diphenhydramine, a diuretic (eg, furosemide), an ergot alkaloid (eg, ergotamine), levothyroxine, a monoamine oxidase inhibitors (MAOI) (eg, phenelzine), or a tricyclic antidepressant (eg, amitriptyline). Epinephrine may not work as well to treat a severe reaction if you are taking any of these medicines

Some MEDICINES MAY INTERACT with Grastek. However, no specific interactions with Grastek are known at this time.

Ask your health care provider if Grastek may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use Grastek:

Use Grastek as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • Grastek comes with an extra patient information sheet called a Medication Guide. Read it carefully. Read it again each time you get Grastek refilled.
  • You will have to take the first dose of Grastek at your doctor's office, hospital, or clinic. Contact your health care provider if you have any questions.
  • Do not remove the tablet from the blister until you are ready to take Grastek. Make sure that your hands are dry when you open the blister pack.
  • Do not swallow, crush, or chew. Place the tablet under your tongue and allow it to dissolve for at least 1 minute before swallowing.
  • Wash your hands after taking Grastek.
  • Do not eat or drink while the tablet is dissolving or for 5 minutes after it has dissolved.
  • If you miss a dose of Grastek, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once. If you miss more than 1 day, call your doctor to find out what to do.
Ask your health care provider any questions you may have about how to use Grastek.

Important safety information:

  • Grastek will not help relieve allergy symptoms if you already have them. Discuss any questions or concerns with your doctor.
  • You will need to start taking Grastek at least 12 weeks before grass pollen season starts unless your doctor has told you otherwise. Continue to take Grastek as your doctor has told you.
  • If you have asthma and you have trouble breathing or your asthma gets harder to control, call your doctor right away.
  • PREGNANCY and BREAST-FEEDING: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using Grastek while you are pregnant. It is not known if this medicine is found in breast milk. If you are or will be breast-feeding while you use Grastek, check with your doctor. Discuss any possible risks to your baby.

Possible side effects of Grastek:

All medicines may cause side effects, but many people have no, or minor side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Itching in the ear, mouth, or tongue; numbness or tingling in the mouth; throat irritation.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest or throat; swelling of the mouth, face, lips, throat, or tongue); chest pain; dizziness or fainting; fast or weak heartbeat; flushing; heartburn; pain with swallowing; severe or persistent coughing; severe or persistent diarrhea, stomach cramps or pain, or vomiting; severe or persistent mouth or throat irritation; shortness of breath or wheezing; trouble speaking or swallowing.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately.

Proper storage of Grastek:

Store Grastek in the original package at room temperature, between 59 and 86 degrees F (15 and 30 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. Keep Grastek out of the reach of children and away from pets.

General information:

  • If you have any questions about Grastek, please talk with your doctor, pharmacist, or other health care provider.
  • Grastek is to be used only by the patient for whom it is prescribed. Do not share it with other people.
  • If your symptoms do not improve or if they become worse, check with your doctor.
  • Check with your pharmacist about how to dispose of unused medicine.

This information should not be used to decide whether or not to take Grastek or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about Grastek. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to Grastek. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your health care provider for complete information about the risks and benefits of using Grastek.

Review Date: August 8, 2016

Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using this medicine.

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