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Grastek Side Effects

Generic Name: timothy grass pollen allergen extract

Note: This document contains side effect information about timothy grass pollen allergen extract. Some of the dosage forms listed on this page may not apply to the brand name Grastek.

In Summary

Common side effects of Grastek include: mouth edema, throat irritation, and pruritus of ear. See below for a comprehensive list of adverse effects.

For the Consumer

Applies to timothy grass pollen allergen extract: sublingual tablet

Along with its needed effects, timothy grass pollen allergen extract (the active ingredient contained in Grastek) 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

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

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

Uncommon (0.1% to 1%): Systemic allergic reactions (including anaphylaxis)
Postmarketing reports: Anaphylactic reaction, angioedema[Ref]

Respiratory

Very common (10% or more): Throat irritation (up to 22.6%)
Common (1% to 10%): Pharyngeal edema, dry throat, oropharyngeal pain, nasal discomfort, throat tightness, dyspnea, pharyngeal erythema, cough, nasal congestion, sneezing
Uncommon (0.1% to 1%): Rhinorrhea, dysphonia
Postmarketing reports: Asthma exacerbation, hoarseness, laryngitis, induced asthma exercise, decreased forced expiratory volume, hyperventilation, laryngeal discomfort, decreased oxygen saturation, decreased peak expiratory flow rate, pneumonia, respiratory distress, status asthmaticus, decreased vital capacity, wheezing[Ref]

Cardiovascular

Common (1% to 10%): Chest discomfort
Postmarketing reports: Chest pressure, increased heart rate, irregular heart rate, hypotension[Ref]

Dermatologic

Common (1% to 10%): Pruritus, urticaria
Postmarketing reports: Facial erythema, rash[Ref]

Gastrointestinal

Very common (10% or more): Oral pruritus ( up to 26.7%), Lip pruritus (up to 11.1%), mouth edema ( up to 11.1%)
Common (1% to 10%): Lip pruritus, oral paresthesia, tongue pruritus, lip swelling, swollen tongue, dyspepsia, oral hypoesthesia, nausea, oral discomfort, oral mucosal erythema, lip edema, glossitis, stomatitis, tongue disorder, tongue edema, glossodynia, dysphagia, palatal edema, glossodynia
Uncommon (0.1% to 1%): Abdominal pain, gastroesophageal reflux, mouth swelling, oral/pharyngeal itching
Postmarketing reports: Oral ulceration, ulcerative colitis exacerbation, diarrhea, eosinophilic esophagitis, oral pain, throat pruritus, vomiting[Ref]

Nervous system

Common (1% to 10%): Headache
Postmarketing reports: Altered state of consciousness, difficulty speaking, dizziness, drowsiness, tremor[Ref]

Other

Very common (10% or more): Ear pruritus (up to 12.5%)
Common (1% to 10%): Fatigue
Uncommon (0.1% to 1%): Ear itching
Postmarketing reports: facial edema, sensation of foreign body, neck swelling[Ref]

References

1. "Product Information. Grastek (timothy grass pollen allergen extract)." Merck & Company Inc, Whitehouse Station, NJ.

Further information

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.

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