Dosing and uses of Ragwitek (ragweed allergen extract)
Adult dosage forms and strengths
sublingual tablet
- 12 Amb a 1-U (~12mcg/tablet)
Allergic Rhinitis
Indicated as immunotherapy for short ragweed (Ambrosia artemisiifolia) pollen-induced allergic rhinitis (with or without conjunctivitis) confirmed by positive skin test or in vitro testing for ragweed-specific IgE antibodies
Initiate treatment 12 weeks before the expected onset of ragweed pollen season and maintain it throughout the season
18-65 years: 1 tablet SL qDay; give 1st dose in physician’s office and observe for 30 min
>65 years: Not approved
Administration
Instruct patients to avoid swallowing for about 1 minute following SL administration
Wash hands after handling the tablet
Do not take with food or beverage; avoid food or beverages for 5 minutes after taking the SL tablet
Pediatric dosage forms and strengths
<18 years: Safety and efficacy not established
Geriatric dosage forms and strengths
Not approved for persons older than 65 years
Ragwitek (ragweed allergen extract) adverse (side) effects
>10%
Throat irritation (16.6%)
Oral pruritus (10.9%)
Ear pruritus (10.4%)
1-10%
Oral paraesthesia (10%)
Mouth edema (6.1%)
Tongue pruritus (5.1%)
Lip swelling (3%)
Swollen tongue (2.9%)
Skin pruritus (1.8%)
Lip pruritus (1.5%)
Dry mouth (1.4%)
Tongue edema (1.3%)
Oropharyngeal pain (1.5%)
Throat tightness (1.3%)
Nausea (1.1%)
Palatal edema (1.1%)
Dysphagia (1%)
Chest discomfort (1%)
Warnings
Black box warnings
Can cause life-threatening allergic reactions (eg, anaphylaxis, severe laryngopharyngeal edema)
Do not administer to patients with severe, unstable, or uncontrolled asthma
Administer 1st dose in a doctor’s office and observe patient for at least 30 minutes
Patients should be prescribed autoinjectable epinephrine, trained on its appropriate use, and instructed to seek immediate medical care upon its use
May not be suitable for patients with certain underlying medical conditions that may reduce their ability to survive a serious allergic reaction (eg, markedly compromised lung function [either chronic or acute], unstable angina, recent MI, significant arrhythmia, uncontrolled hypertension)
Patients taking drugs that inhibit bronchodilator or epinephrine effects (eg, beta-blockers, alpha-blockers, ergot alkaloids) may be unresponsive to the usual doses of epinephrine
May not be suitable for patients taking drugs that potentiate epinephrine effect (eg, TCAs, levothyroxine, MAOIs, chlorpheniramine, diphenhydramine)
Carefully observe patients who receive epinephrine while taking cardiac glycosides or diuretics for the development of cardiac arrhythmias
Contraindications
Severe, unstable, or uncontrolled asthma
History of any severe systemic or local reaction to sublingual allergen immunotherapy
History of eosinophilic esophagitis
Hypersensitivity to inactive ingredients (gelatin, mannitol, sodium hydroxide)
Cautions
Potential for severe allergic reaction (see Black box warnings and Contraindications)
Must be prescribed with autoinjectable epinephrine (see Black box warnings)
Not studied with moderate or severe asthma or any subjects who required daily medication
Withhold dose if patient experiencing an acute asthma exacerbation; re-evaluate patients with recurrent asthma exacerbations and consider discontinuing
Can cause local reaction in the mouth or throat that could compromise the upper airway
Eosinophilic esophagitis has been reported in association with SL tablet immunotherapy
Not studied in individuals receiving concomitant allergen immunotherapy
Stop treatment and allow complete healing of the oral cavity in patients with oral inflammation (eg, oral lichen planus, mouth ulcers or thrush) or oral wounds (eg, oral surgery, dental extraction)
Risks may be increased when treatment is initiated during the ragweed pollen season
Pregnancy and lactation
Pregnancy category: C
Because systemic and local adverse reactions with immunotherapy may be poorly tolerated during pregnancy, ragweed allergen extract should be used during pregnancy only if clearly needed
Lactation: Unknown if distributed in human breast milk; caution advised
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Ragwitek (ragweed allergen extract)
Mechanism of action
Precise mechanism of allergen immunotherapy is not known
Allergen immunotherapy SL tablet consisting of purified and calibrated extract of ragweed allergen (Ambrosia artemisiifolia)
