Allergy Shot Frequency
During the build-up phase, allergy shots should be administered 1 to 3 times per week, and once maintenance dosing is achieved, injections are given every 2 to 4 weeks for inhalant allergens. 1
Build-Up Phase Frequency
Administer injections 1 to 3 times per week during the initial build-up phase, with the most common schedule being 1 to 2 times weekly. 1
The build-up phase typically lasts 3 to 6 months depending on injection frequency—approximately 3 months with twice-weekly dosing and 6 months with once-weekly dosing. 1
Injections can be given as frequently as daily (with at least 1 day spacing) without increased systemic reaction risk if there is urgency to reach maintenance dosing, such as approaching allergy season. 1
Accelerated Build-Up Options
Cluster immunotherapy involves 2-3 injections per visit on non-consecutive days, achieving maintenance dose within 4 to 8 weeks rather than the conventional 3 to 6 months. 1
Rush protocols exist but carry higher systemic reaction risk for aeroallergens (though not for Hymenoptera venom immunotherapy). 1
Maintenance Phase Frequency
Once maintenance dose is reached, extend intervals progressively up to every 4 weeks for inhalant allergens. 1, 2
For Hymenoptera venom immunotherapy, intervals can be extended up to 8 weeks, with some patients tolerating even longer intervals without loss of efficacy. 1, 2
A 3-week interval represents an appropriate middle ground within the standard maintenance window for most patients. 2
Critical Dose Adjustments
When to Reduce Dose or Frequency
Always reduce the dose after a systemic reaction if continuing immunotherapy, typically returning to a previously tolerated dose or lower if the reaction was severe. 1
Reduce or hold dose increases during high allergen exposure periods (peak pollen season) in highly sensitive patients experiencing symptom exacerbations, as this increases systemic reaction risk. 1
Reduce the dose when injection intervals are prolonged beyond the scheduled timeframe, as this is standard practice to maintain safety. 1
Safety Caveats
Never extend to 3-week intervals for patients with a history of systemic reactions or during high pollen seasons in poorly controlled, highly sensitive patients. 2
Patients with asthma and FEV1 below 70% predicted or unstable asthma should not receive injections due to higher systemic reaction risk. 3
All injections require a 30-minute post-injection observation period to monitor for systemic reactions. 2