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Grastek

Generic Name: Grass Pollen Allergen Extract (Timothy Grass) (GRAS POL uhn al er juhn EK strakt TIM oh thee GRAS)
Brand Name: Grastek

Medically reviewed on May 2, 2018.

Warning

  • Very bad and sometimes deadly allergic side effects have rarely happened. Talk with your doctor.
  • The first dose will be given in a doctor's office.
  • Your doctor will give you another drug (epinephrine) to use in case of an allergic reaction. Be sure you know how and when to use it. Certain drugs may make epinephrine not work as well or raise the chance of side effects. This includes some drugs used to treat depression, heart problems, or high blood pressure. There are many drugs that interact with epinephrine. Talk with your doctor or pharmacist to make sure it is safe to take epinephrine with all of your drugs.
  • Do not take Grastek (grass pollen allergen extract (timothy grass)) if you have very bad asthma or asthma that is not controlled.

Uses of Grastek:

  • It is used to treat allergies caused by Timothy grass pollen.

What do I need to tell my doctor BEFORE I take Grastek?

  • If you have an allergy to Grastek (grass pollen allergen extract (timothy grass)) or any part of Grastek (grass pollen allergen extract (timothy grass)).
  • If you are allergic to any drugs like this one, any other drugs, foods, or other substances. Tell your doctor about the allergy and what signs you had, like rash; hives; itching; shortness of breath; wheezing; cough; swelling of face, lips, tongue, or throat; or any other signs.
  • If you ever had a very bad allergic reaction.
  • If you have ever had eosinophilic esophagitis.

This is not a list of all drugs or health problems that interact with Grastek (grass pollen allergen extract (timothy grass)).

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take Grastek (grass pollen allergen extract (timothy grass)) with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take Grastek?

  • Tell all of your health care providers that you take Grastek (grass pollen allergen extract (timothy grass)). This includes your doctors, nurses, pharmacists, and dentists.
  • This medicine will not help allergy signs get better if the signs are already present. Talk with the doctor.
  • If you are getting allergy shots or taking other drugs like this one under the tongue, talk with your doctor. Using these drugs at the same time may raise the chance of a very bad allergic reaction.
  • This medicine is most useful if started before contact with the allergen. Take at least 12 weeks before.
  • Take Grastek (grass pollen allergen extract (timothy grass)) as long as you were told by your doctor.
  • If you have asthma and you have trouble breathing or your asthma gets harder to control, call your doctor right away.
  • Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using Grastek (grass pollen allergen extract (timothy grass)) while you are pregnant.
  • Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.

How is this medicine (Grastek) best taken?

Use Grastek (grass pollen allergen extract (timothy grass)) as ordered by your doctor. Read all information given to you. Follow all instructions closely.

  • Be sure your hands are dry before you touch Grastek (grass pollen allergen extract (timothy grass)).
  • Do not take Grastek (grass pollen allergen extract (timothy grass)) out of the blister pack until you are ready to take it. Take Grastek (grass pollen allergen extract (timothy grass)) right away after opening the blister pack. Do not store the removed drug for future use.
  • Place under tongue and let melt all the way. Do not chew, suck or swallow tablet.
  • Do not swallow for at least 1 minute after putting Grastek (grass pollen allergen extract (timothy grass)) in your mouth.
  • Do not eat or drink while the tablet is melting or for 5 minutes after the tablet melts.
  • Wash your hands after use.

What do I do if I miss a dose?

  • Skip the missed dose and go back to your normal time.
  • Do not take 2 doses at the same time or extra doses.
  • If you miss more than 1 day of taking Grastek (grass pollen allergen extract (timothy grass)), talk with your doctor.

See also: Dosage Information (in more detail)

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Trouble swallowing or speaking.
  • Pain with swallowing.
  • Heartburn.
  • Chest pain or pressure, a fast heartbeat, or passing out.
  • Dizziness.
  • Flushing.
  • Shortness of breath.
  • High-pitched abnormal breathing sound.
  • Cough that does not go away.
  • Very loose stools (diarrhea).
  • Very upset stomach or throwing up.
  • Stomach cramps.
  • Very bad belly pain.
  • Very bad mouth irritation.
  • Redness or white patches in mouth or throat.
  • Very bad throat irritation.

What are some other side effects of Grastek?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

  • Itching in the ear, mouth, or tongue.
  • Numbness or tingling in the mouth.
  • Throat irritation.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.

See also: Side effects (in more detail)

If OVERDOSE is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out Grastek?

  • Store in the original container at room temperature.
  • Store in a dry place. Do not store in a bathroom.
  • Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
  • Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.

Consumer information use

  • If your symptoms or health problems do not get better or if they become worse, call your doctor.
  • Do not share your drugs with others and do not take anyone else's drugs.
  • Keep a list of all your drugs (prescription, natural products, vitamins, OTC) with you. Give this list to your doctor.
  • Talk with the doctor before starting any new drug, including prescription or OTC, natural products, or vitamins.
  • This medicine comes with an extra patient fact sheet called a Medication Guide. Read it with care. Read it again each time Grastek (grass pollen allergen extract (timothy grass)) is refilled. If you have any questions about Grastek (grass pollen allergen extract (timothy grass)), please talk with the doctor, pharmacist, or other health care provider.
  • If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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