Introduction

Allergen immunotherapy tablets (sublingual tablets) are FDA‑approved, single‑allergen therapies for environmental allergic rhinitis/conjunctivitis. In the U.S., four tablets are marketed: Grastek (Timothy grass), Oralair (5‑grass mix), Ragwitek (short ragweed), and Odactra (house dust mite). U.S. labels uniformly require the first dose to be administered under medical supervision with at least 30 minutes of observation and an epinephrine auto‑injector prescribed for home use. Tablets are not for immediate symptom relief.

Who qualifies and when to start

• Age window (all tablets): approved for patients 5 through 65 years.

• Seasonal start windows (by label):

• Grastek: start at least 12 weeks before expected grass season; continue through the season. Optionally take daily for 3 consecutive years to sustain effectiveness into the fourth season.

• Oralair: start 4 months before expected grass season; continue throughout the season.

• Ragwitek: start at least 12 weeks before expected ragweed season; continue throughout the season.

• Odactra: daily, year‑round (no pre‑season timing). As of February 28, 2025, FDA expanded use to ages 5–11; Odactra is now approved for 5–65 years.

FDA‑aligned product snapshots

Grastek (Timothy grass pollen allergen extract)

• Indication: grass pollen‑induced allergic rhinitis with or without conjunctivitis (Timothy or cross‑reactive grasses).

• Ages: 5–65 years.

• When to start: ≥12 weeks before grass season; continue through season; 3 years of daily dosing can sustain benefit into a fourth season.

• First dose and safety: first dose under medical supervision with ≥30‑minute observation; prescribe auto‑injectable epinephrine for home use. Contraindicated in severe, unstable, or uncontrolled asthma; history of severe systemic/SLIT reactions; eosinophilic esophagitis.

Oralair (mixed 5‑grass pollen allergen extract)

• Indication: grass pollen‑induced allergic rhinitis/conjunctivitis to any of the five included grasses.

• Ages: 5–65 years.

• When to start: 4 months before expected grass season; continue through season.

• First dose and safety: first dose under medical supervision with ≥30‑minute observation; epinephrine auto‑injector should be prescribed. Contraindications mirror other SLIT tablets (e.g., severe/uncontrolled asthma, prior severe systemic/SLIT reaction, eosinophilic esophagitis).

Ragwitek (short ragweed pollen allergen extract)

• Indication: short ragweed pollen‑induced allergic rhinitis/conjunctivitis.

• Ages: 5–65 years.

• When to start: ≥12 weeks before ragweed season; continue through season.

• First dose and safety: first dose under medical supervision with ≥30‑minute observation; prescribe auto‑injectable epinephrine. Contraindicated in severe, unstable, or uncontrolled asthma; prior severe systemic/SLIT reaction; eosinophilic esophagitis.

Odactra (house dust mite allergen extract)

• Indication: HDM‑induced allergic rhinitis with or without conjunctivitis; daily, year‑round dosing.

• Ages: 5–65 years (pediatric expansion announced February 28, 2025).

• First dose and safety: first dose under medical supervision with ≥30‑minute observation; prescribe epinephrine. Contraindications include severe, unstable, or uncontrolled asthma; history of severe systemic or severe local SLIT reaction; eosinophilic esophagitis.

Quick comparison (label facts)

Tablet	Allergen/Indication	Ages (years)	When to start	Dosing pattern	First dose supervised + epinephrine
Grastek	Timothy grass (and cross‑reactive grasses) AR/C	5–65	≥12 weeks before grass season	Daily through season (option: 3 yrs daily for sustained effect)	Yes; prescribe epinephrine
Oralair	5‑grass mix AR/C	5–65	4 months before grass season	Daily through season	Yes; prescribe epinephrine
Ragwitek	Short ragweed AR/C	5–65	≥12 weeks before ragweed season	Daily through season	Yes; prescribe epinephrine
Odactra	House dust mite AR/C	5–65	No pre‑season; start any time	Daily year‑round	Yes; prescribe epinephrine

Label sources: Grastek PI; Oralair PI; Ragwitek PI; Odactra PI/FDA update (Feb 28, 2025).

Safety requirements common to all SLIT tablets

• Boxed warning: life‑threatening allergic reactions (anaphylaxis, severe laryngopharyngeal edema) are possible; initial dose must be supervised and patients must have access to auto‑injectable epinephrine and be trained in its use.

• Key contraindications (class‑consistent): severe, unstable or uncontrolled asthma; history of severe systemic reaction to SLIT or severe local SLIT reaction; eosinophilic esophagitis; hypersensitivity to excipients.

• Not for acute symptom relief; do not take with food or drink and avoid eating/drinking for 5 minutes after dosing (per labels).

When Wyndly recommends tablets vs. drops

• Tablets are ideal when a single, label‑covered allergen is the main driver (grass, ragweed, or dust‑mite), and you can start early enough (seasonal products). For poly‑sensitized patients or allergens without tablet options (e.g., many trees, pet dander, molds), Wyndly typically recommends custom sublingual immunotherapy drops, which can treat multiple allergens simultaneously at home. See: Sublingual Immunotherapy: drops and tablets and Allergy drops. Evidence summaries on our site note that drops can address multiple allergens at once, whereas tablets treat one at a time.

Getting started with Wyndly

• Meet a Wyndly physician to confirm eligibility and discuss timing. If a tablet is chosen, your doctor will plan the required first‑dose supervision and prescribe epinephrine; if drops are a better fit, your custom plan will be shipped for at‑home use with ongoing physician support. Learn about Wyndly immunotherapy and our pollen SLIT program.

References (labels and FDA pages)

1) GRASTEK Prescribing Information (Timothy grass) and FDA allergenics page. 2) ORALAIR Prescribing Information / dosing and HCP guidance. 3) RAGWITEK Prescribing Information and FDA allergenics page. 4) ODACTRA Prescribing Information and FDA pediatric expansion notice (Feb 28, 2025).