"By Matt McMillen
WebMD Health News
Reviewed by Brunilda Nazario, MD
April 9, 2015 -- Spring is finally here, and with it comes tree pollen. For people with allergies, that could spell misery. But despite the hars"...
Severe Allergic Reactions
GRASTEK can cause systemic allergic reactions including anaphylaxis which may be lifethreatening. In addition, GRASTEK can cause severe local reactions, including laryngopharyngeal swelling, which can compromise breathing and be life-threatening. Educate patients to recognize the signs and symptoms of these allergic reactions and instruct them to seek immediate medical care and discontinue therapy should any of these occur. Allergic reactions may require treatment with epinephrine. [See Epinephrine]
Administer the initial dose of GRASTEK in a healthcare setting under the supervision of a physician with experience in the diagnosis and treatment of allergic diseases and prepared to manage a lifethreatening systemic or local allergic reaction. Observe patients in the office for at least 30 minutes following the initial dose of GRASTEK.
Prescribe auto-injectable epinephrine to patients receiving GRASTEK. Instruct patients to recognize the signs and symptoms of a severe allergic reaction and in the proper use of emergency auto-injectable epinephrine. Instruct patients to seek immediate medical care upon use of auto-injectable epinephrine and to stop treatment with GRASTEK. [See PATIENT INFORMATION]
See the epinephrine package insert for complete information.
GRASTEK may not be suitable for patients with certain medical conditions that may reduce the ability to survive a serious allergic reaction or increase the risk of adverse reactions after epinephrine administration. Examples of these medical conditions include but are not limited to: markedly compromised lung function (either chronic or acute), unstable angina, recent myocardial infarction, significant arrhythmia, and uncontrolled hypertension.
GRASTEK may not be suitable for patients who are taking medications that can potentiate or inhibit the effect of epinephrine. These medications include:
Beta-adrenergic blockers: Patients taking beta-adrenergic blockers may be unresponsive to the usual doses of epinephrine used to treat serious systemic reactions, including anaphylaxis. Specifically, beta-adrenergic blockers antagonize the cardiostimulating and bronchodilating effects of epinephrine.
Alpha-adrenergic blockers, ergot alkaloids: Patients taking alpha-adrenergic blockers may be unresponsive to the usual doses of epinephrine used to treat serious systemic reactions, including anaphylaxis. Specifically, alpha-adrenergic blockers antagonize the vasoconstricting and hypertensive effects of epinephrine. Similarly, ergot alkaloids may reverse the pressor effects of epinephrine.
Tricyclic antidepressants, levothyroxine sodium, monoamine oxidase inhibitors and certain antihistamines: The adverse effects of epinephrine may be potentiated in patients taking tricyclic antidepressants, levothyroxine sodium, monoamine oxidase inhibitors, and the antihistamines chlorpheniramine, and diphenhydramine.
Cardiac glycosides, diuretics: Patients who receive epinephrine while taking cardiac glycosides or diuretics should be observed carefully for the development of cardiac arrhythmias.
Upper Airway Compromise
GRASTEK can cause local reactions in the mouth or throat that could compromise the upper airway [See ADVERSE REACTIONS]. Consider discontinuation of GRASTEK in patients who experience persistent and escalating adverse reactions in the mouth or throat.
Eosinophilic esophagitis has been reported in association with sublingual tablet immunotherapy [See CONTRAINDICATIONS and ADVERSE REACTIONS]. Discontinue GRASTEK and consider a diagnosis of eosinophilic esophagitis in patients who experience severe or persistent gastro-esophageal symptoms including dysphagia or chest pain.
GRASTEK has not been studied in subjects with moderate or severe asthma or any subjects who required daily medication to treat asthma.
Withhold immunotherapy with GRASTEK if the patient is experiencing an acute asthma exacerbation. Reevaluate patients who have recurrent asthma exacerbations and consider discontinuation of GRASTEK.
Concomitant Allergen Immunotherapy
GRASTEK has not been studied in subjects who are receiving concomitant allergen immunotherapy. Concomitant dosing with other allergen immunotherapy may increase the likelihood of local or systemic adverse reactions to either subcutaneous or sublingual allergen immunotherapy.
Stop treatment with GRASTEK to allow complete healing of the oral cavity in patients with oral inflammation (e.g., oral lichen planus, mouth ulcers or thrush) or oral wounds, such as those following oral surgery or dental extraction.
Patient Counseling Information
Advise patients to read the FDA-approved patient labeling (Medication Guide) and to keep GRASTEK and all medicines out of the reach of children.
Severe Allergic Reactions
Advise patients that GRASTEK may cause life-threatening systemic or local allergic reactions, including anaphylaxis. Educate patients about the signs and symptoms of these allergic reactions [See WARNINGS AND PRECAUTIONS]. The signs and symptoms of a severe allergic reaction may include: syncope, dizziness, hypotension, tachycardia, dyspnea, wheezing, bronchospasm, chest discomfort, cough, abdominal pain, vomiting, diarrhea, rash, pruritus, flushing, and urticaria.
Ensure that patients have auto-injectable epinephrine and instruct patients in its proper use. Instruct patients who experience a severe allergic reaction to seek immediate medical care, discontinue GRASTEK, and resume treatment only when advised by a physician to do so. [See WARNINGS AND PRECAUTIONS]
Advise patients to read the patient information for epinephrine.
Inform patients that the first dose of GRASTEK must be administered in a healthcare setting under the supervision of a physician and that they will be monitored for at least 30 minutes to watch for signs and symptoms of a life-threatening systemic or local allergic reaction [See WARNINGS AND PRECAUTIONS]
Because of the risk of upper airway compromise, instruct patients with persistent and escalating adverse reactions in the mouth or throat to discontinue GRASTEK and to contact their healthcare professional. [See WARNINGS AND PRECAUTIONS].
Because of the risk of eosinophilic esophagitis, instruct patients with severe or persistent symptoms of esophagitis to discontinue GRASTEK and to contact their healthcare professional. [See WARNINGS AND PRECAUTIONS].
Inform parents/guardians that GRASTEK should only be administered to children under adult supervision [See DOSAGE AND ADMINISTRATION].
Instruct patients with asthma that if they have difficulty breathing or if their asthma becomes difficult to control, they should stop taking GRASTEK and contact their healthcare professional immediately [See WARNINGS AND PRECAUTIONS].
Instruct patients to carefully remove the foil from the blister unit with dry hands and then take the sublingual tablet immediately by placing it under the tongue where it will dissolve. Also instruct patients to wash their hands after handling the tablet, and to avoid food or beverages for 5 minutes after taking the tablet. [See DOSAGE AND ADMINISTRATION]
Carcinogenesis, Mutagenesis, Impairment Of Fertility
No studies have been performed in animals to evaluate the carcinogenic potential of GRASTEK.
A fertility study in mice revealed no evidence of impaired fertility due to Timothy grass pollen allergen extract.
Use In Specific Populations
Pregnancy Category B
Reproductive and developmental toxicity studies performed in female mice have revealed no evidence of harm to the fetus due to GRASTEK. In these studies, the effect of Timothy grass (Phleum pratense) pollen allergen extract, the active component of GRASTEK, on embryo-fetal development was evaluated. Mice were administered approximately 460,000 BAU/kg/day of Timothy grass pollen allergen extract by oral gavage on days 0 to 15 of gestation. A dose of 460,000 BAU/kg/day of Timothy grass pollen allergen extract corresponds to approximately 8,200-fold a human dose on a BAU/kg/day basis. No adverse effects on embryo-fetal development were observed. There are, however, no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, GRASTEK should be used during pregnancy only if clearly needed.
Because systemic and local adverse reactions with immunotherapy may be poorly tolerated during pregnancy, GRASTEK should be used during pregnancy only if clearly needed.
It is not known if GRASTEK is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when GRASTEK is administered to a nursing woman.
Efficacy and safety of GRASTEK have been established in children and adolescents 5 through 17 years of age.
The safety and efficacy in pediatric patients below 5 years of age have not been established.
There is no clinical trial experience with GRASTEK in patients over 65 years of age.
Last reviewed on RxList: 5/1/2014
This monograph has been modified to include the generic and brand name in many instances.
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