Allergen immunotherapy (AIT) is an effective treatment for allergic rhinitis/conjunctivitis (AR/AC), allergic asthma, atopic dermatitis with aeroallergen sensitization (ie, dust mites), and stinging-insect hypersensitivity. Patients should demonstrate specific IgE antibodies to relevant allergens to which they are allergic, either by skin testing or appropriate in vitro tests. There are no specific age limits; however, children should be able to communicate effectively, and comorbidities in elderly should be considered. Duration of therapy should be patient individualized, but most guidelines recommend 3–5 years of maintenance therapy for aeroallergens (repeat skin or blood testing not recommended). AIT may be given indefinitely for severe stinging-insect hypersensitivity, particularly in patients with severe reactions or systemic mastocytosis.

Perennial SCIT

two phases: a build-up phase (also known as up-dosing or induction) and a maintenance phase.

Build up/Induction/Updosing - 4 - 6 months

During the build-up phase, the patient receives weekly injections, starting with a very low dose, with gradual increases in dose over the course of 4–6 months. The frequency of injections during this phase generally ranges from 1 to 3 times per week, although more rapid build-up schedules are sometimes used. After this period, the patient has usually built up sufficient tolerance to the allergen such that a maintenance (therapeutic) dose has been reached.

Maintenance phase

During the maintenance phase, the patient generally receives injections of the maintenance dose every 4 weeks for inhalant allergens, usually for a period of 3–5 years. After this period, many patients experience a prolonged, protective effect and, therefore, consideration can be given to stopping therapy, depending on risk factors for recurrence in the case of venom immunotherapy.

TODO: double check this: During allergen season, no updosing of buildup phase for that allergen, just monthly. afterwards buildup until mainenance.

NB: each time the vials are switched the dose has to be cut at least 50% because there is degradation of the vials once the diluant is added. caution: manufactuer vials lot to lot can also change, which is also why the dose is cut can be significant differences in potency

Seasonal AIT

Sometimes it is performed for seasonal allergens on a seasonal basis. For example, you may start giving tree AIT in December of Janurary (2-3 months prior to the season beginning), before stopping once the season is over.

Differences between SLIT and SCIT

• Allergens available. SLIT is only for grasses (Orarlair, Grastek), birch (Itaultek), dust mite (Acaratax), ragweed (Ragwitek)
• Risk of anaphylaxis is essentially zero for SLIT but ~1/1000 for SCIT

To my knowledge: no head to head efficacy comparison between seasonal AIT and perennial

SCIT contraindications

BB ACEi relative contraindicatoins

SCIT side effects

SLIT contraindications

SLIT side effects

Common:

Uncommon:

Dust mite SLIT

Acarizax

Extracts for D. farinae, D. pteronyssinus. No lactose, but fish gelatin. Dose: OD First dose: in office Timing of initiation: anytime Peel, not pop the package (wafers very thin and fragile) Generally take in AM -- no food or water for 15 mins (advice from Western elective -- ALK package says 5 mins) Miss dose: don't double up Ages: studies on adults 18-65 -- TODO: double check monographs. Off-label used in children. Pregnancy: TODO Patient information / monograph: ALK 2022

orlistat

Monitoring: