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Grastek

Generic Name: timothy grass pollen allergen extract (TIM oh thee grass PAW len AL er gen EX tract)
Brand Name: Grastek

What is Grastek (timothy grass pollen allergen extract)?

Timothy grass pollen allergen extract is made from certain pollens that can cause seasonal allergies (hay fever).

Timothy grass pollen allergen extract is used to help your body develop an immunity to certain pollens that can cause allergy symptoms such as sneezing, itching, and watery eyes. This medicine is for use in adults up to age 65, and children who are at least 5 years old.

This medicine will not provide immediate relief from allergy symptoms.

Timothy grass pollen allergen extract may also be used for purposes not listed in this medication guide.

What is the most important information I should know about Grastek (timothy grass pollen allergen extract)?

You should not use this medicine if you have uncontrolled asthma, or if you have a history of allergic reaction to a pollen-extract medicine, or allergic reaction that affected your esophagus.

You may not be able to use timothy grass pollen allergen extract if you have certain medical conditions, such as breathing problems, heart disease, or high blood pressure. This medicine also may not be safe for you if you take certain medicines.

Timothy grass pollen allergen extract may cause a severe allergic reaction. Your doctor will give you the first dose and watch you closely to make sure you do not have a reaction.

Your doctor may also prescribe epinephrine (Epi-Pen) to keep with you in case you ever have an allergic reaction to timothy grass pollen allergen extract.

Stop taking this medicine and get emergency medical help if you have signs of an allergic reaction: severe dizziness, feeling like you might pass out; fast heart rate, cough, chest tightness, wheezing, trouble breathing; stomach pain, vomiting, diarrhea; hives, itching, flushing (warmth, redness, or tingly feeling); swelling of your face, lips, tongue, or throat.

What should I discuss with my healthcare provider before taking Grastek (timothy grass pollen allergen extract)?

You should not use timothy grass pollen allergen extract if you have ever had an allergic reaction to similar pollen-extract medicines, or if you have:

  • severe or uncontrolled asthma; or

  • a history of allergic reaction that affected your esophagus (the tube that connects your mouth and stomach) and caused heartburn or trouble swallowing.

To make sure timothy grass pollen allergen extract is safe for you, tell your doctor if you have:

  • breathing problems;

  • heart disease;

  • uncontrolled high blood pressure;

  • mouth sores, swollen gums, or other wounds or irritations inside your mouth;

  • if you take an antidepressant or migraine headache medicine; or

  • if you take medicine to treat heart problems, high blood pressure, or a prostate disorder.

FDA pregnancy category B. Timothy grass pollen allergen extract is not expected to harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment.

It is not known whether timothy grass pollen allergen extract passes into breast milk or if it could harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

Timothy grass pollen allergen extract should not be given to a child younger than 5 years old.

This medicine is not for use in people older than 65.

How should I take Grastek (timothy grass pollen allergen extract)?

Your doctor may perform an allergy skin test or blood test to make sure you are allergic to the specific pollen contained in this medicine.

Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.

Your doctor may want to give your first dose of this medicine in a clinic setting. You should be watched closely for at least 30 minutes after taking your first dose, to make sure you do not have an allergic reaction.

Timothy grass pollen allergen extract is a sublingual tablet that dissolves under your tongue. Do not chew this tablet or swallow it whole.

To take the sublingual tablet:

  • Keep the tablet in its blister pack until you are ready to take it. Open the package and peel back the foil.

  • Use dry hands to remove the tablet and place it in your mouth.

  • Place the sublingual tablet under your tongue and allow it to dissolve completely.

  • Do not swallow for at least 1 minute. Do not eat or drink anything for at least 5 minutes.

Wash your hands after handling the sublingual tablet.

A child using timothy grass pollen extract should be supervised by an adult while taking this medicine.

Timothy grass pollen allergen extract is usually taken once daily throughout allergy season. For best results, start taking this medicine at least 12 weeks before the start of allergy season.

In some cases, you may need to take timothy grass pollen allergen extract every day all year long, for up to 3 years. Follow your doctor's dosing instructions very carefully.

Your doctor may also prescribe epinephrine (Epi-Pen) to keep with you in case you ever have an allergic reaction to timothy grass pollen allergen extract.

If you need oral surgery or dental work, or if you have a mouth injury or infection, you may need to stop using this medicine until your mouth heals. Tell your doctor if the sublingual tablets cause any mouth irritation.

Store tablets in the blister pack at room temperature, away from moisture and heat.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking Grastek (timothy grass pollen allergen extract)?

Ask your doctor before starting any new medicine or treatments, including allergy shots.

Grastek (timothy grass pollen allergen extract) side effects

Timothy grass pollen allergen extract may cause a severe allergic reaction. Stop taking the medicine and get emergency medical help if you have any of these signs of an allergic reaction:

  • severe dizziness or a light-headed feeling (like you might pass out);

  • fast heart rate;

  • stomach pain, vomiting, diarrhea;

  • hives, itching, flushing (warmth, redness, or tingly feeling);

  • cough, chest tightness, wheezing, trouble breathing; or

  • swelling of your face, lips, tongue, or throat.

If you stop taking timothy grass pollen allergen extract after having an allergic reaction, do not start taking the medicine again without your doctor's advice.

Call your doctor at once if you have:

  • severe mouth or throat irritation;

  • breathing problems; or

  • choking feeling, chest pain, trouble swallowing.

Common side effects may include:

  • swelling or itching of your mouth or tongue;

  • throat irritation; or

  • itching in your ears.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect Grastek (timothy grass pollen allergen extract)?

Other drugs may interact with timothy grass pollen allergen extract, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Where can I get more information?

  • Your pharmacist can provide more information about timothy grass pollen allergen extract.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2012 Cerner Multum, Inc. Version: 1.01. Revision Date: 2014-06-24, 6:53:50 AM.

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