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Timothy Grass Pollen Allergen Extract Side Effects

Medically reviewed by Drugs.com. Last updated on Dec 12, 2022.

Applies to timothy grass pollen allergen extract: sublingual tablet.

Important warnings This medicine can cause some serious health issues

Sublingual route (tablet)

Timothy Grass Pollen Allergen Extract can cause life-threatening allergic reactions such as anaphylaxis and severe laryngopharyngeal restriction.

Do not administer Timothy Grass Pollen Allergen Extract to patients with severe, unstable or uncontrolled asthma.

Observe patients in the office for at least 30 minutes following the initial dose.

Prescribe auto-injectable epinephrine, instruct and train patients on its appropriate use, and instruct patients to seek immediate medical care upon its use.

Timothy Grass Pollen Allergen Extract may not be suitable for patients with certain underlying medical conditions that may reduce their ability to survive a serious allergic reaction, or in patients who may be unresponsive to epinephrine or inhaled bronchodilators (eg, those taking beta-blockers).

Serious side effects

Along with its needed effects, timothy grass pollen allergen extract may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking timothy grass pollen allergen extract:

More common

  • itching of the ears, mouth, or tongue
  • numbness or tingling feeling around the mouth
  • sore throat
  • swelling of the mouth

Less common

  • chest discomfort
  • difficult or labored breathing
  • difficulty swallowing
  • hives or welts, itching, or skin rash
  • redness, swelling, or soreness of the tongue or in the mouth
  • runny nose
  • swelling of the lips
  • tightness in the chest

Incidence not known

  • cough
  • dizziness
  • dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  • fast heartbeat
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • sweating
  • unusual tiredness or weakness

Other side effects

Some side effects of timothy grass pollen allergen extract may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Less common

  • acid or sour stomach
  • dry throat
  • headache
  • heartburn
  • nausea

Incidence not known

For healthcare professionals

Applies to timothy grass pollen allergen extract: sublingual tablet.

General

The most common side effects were ear pruritus, oral pruritus, tongue pruritus, mouth edema, and throat irritation.[Ref]

Hypersensitivity

Respiratory

Cardiovascular

Dermatologic

Gastrointestinal

Nervous system

Other

References

1. (2014) "Product Information. Grastek (timothy grass pollen allergen extract)." Merck & Co., Inc

More about timothy grass pollen allergen extract

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Further information

Timothy grass pollen allergen extract side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.