Are immunotherapy doses usually increased week to week?

Allergen Immunotherapy Dosing Schedule

Yes, immunotherapy doses are typically increased weekly during the build-up phase, with 1-2 injections per week being the standard protocol to reach maintenance dose. 1, 2

Standard Build-Up Phase Protocol

The build-up phase of allergen immunotherapy follows a structured approach:

• Frequency: 1-2 injections per week is the conventional schedule 1, 2
• Starting dose: Usually begins at 1:1,000 or 1:10,000 dilution of the maintenance concentration 1
• Progression: Doses gradually increase until reaching maintenance level
• Duration: With this weekly schedule, patients typically reach maintenance dose in 3-6 months 1

Dose Adjustment Considerations

Several factors influence the rate of dose increases:

• Patient sensitivity: More cautious increases for highly sensitive patients 1
• Prior reactions: History of reactions may necessitate slower progression 1
• Concentration being delivered: Smaller percentage increases at higher concentrations 1
• Seasonal exposure: Consider not increasing or even reducing doses during high allergen exposure seasons 1

Alternative Accelerated Schedules

For patients needing to reach maintenance dose more quickly, alternative schedules exist:

1. Cluster immunotherapy:

   • Multiple injections administered in a single visit on non-consecutive days
   • Reaches maintenance in 4-8 weeks 3
   • Higher risk of systemic reactions; premedication recommended 1, 3

2. Rush immunotherapy:

   • Multiple injections at 15-60 minute intervals over 1-3 days 3
   • Reaches maintenance dose very rapidly
   • Highest risk of systemic reactions (up to 73% without premedication) 1
   • Requires extended observation (1.5-3 hours) 1

Safety Considerations

• Systemic reactions: After a systemic reaction, the dose is typically reduced to a previously tolerated level 1
• Missed doses: Dose reduction is necessary when the interval between injections is prolonged 1
• Seasonal adjustments: Consider not increasing or reducing doses during peak allergen seasons 1

Clinical Pearls

• Premedication (typically antihistamines) is strongly recommended before cluster or rush protocols to reduce systemic reaction risk 1
• Venom immunotherapy rush protocols have not shown the same high incidence of systemic reactions as inhalant allergen rush protocols 1
• The most common systemic reaction during rush protocols is flushing 1
• Weekly schedules are considered the safest approach for most patients 1

The weekly build-up schedule remains the most widely used approach due to its favorable safety profile while still providing effective desensitization for most patients.