ABSTRACT
BACKGROUND: Cat extract allergen immunotherapy (AIT) is an effective treatment for cat allergy. The prescribed dose for cat AIT varies among prescribers, despite published data supporting an effective dose range. The original practice parameter published in December 1996 did not recommend a dose of cat allergen, but updates in January 2003 and September 2007 recommend cat extract dose ranges of 2,000 to 3,000 BAU and 1,000 to 4,000 BAU, respectively. OBJECTIVE: To describe the prescribing patterns for cat AIT among practicing allergists in a large health care system and the effect of practice parameters on these patterns. METHODS: A total of 27,788 prescriptions were analyzed to determine the date and amount of maintenance dose cat allergen prescribed. The data were subdivided into periods before and after the 3 published AIT practice parameters. RESULTS: From January 2003 to September 2007, 1,810 prescriptions (18.0%) were written in the recommended range. From September 2007 to May 2009, 3,143 prescriptions (82.6%) were written in the recommended range. Cat AIT maintenance doses were 1,000 to 4,000 BAU 22.1% of the time before January 2003, 61.8% from January 2003 to September 2007, and 82.6% from September 2007 to May 2009. CONCLUSIONS: In this large systemic evaluation of cat AIT prescribing patterns, maintenance dose recommendations in the AIT practice parameters were associated with changes in the prescribing patterns for cat AIT. Most prescriptions for cat AIT were inconsistent with recommended doses in the AIT practice parameters between 2003 and 2007. Dosing within recommended ranges improved after 2007, in part due to a widening of the recommended dose range.
Subject(s)
Allergens/therapeutic use , Cell Extracts/therapeutic use , Desensitization, Immunologic , Hypersensitivity/epidemiology , Practice Patterns, Physicians'/statistics & numerical data , Allergens/immunology , Animals , Cats , Cell Extracts/immunology , Follow-Up Studies , Humans , Hypersensitivity/drug therapy , Hypersensitivity/immunology , Practice Guidelines as Topic , Practice Patterns, Physicians'/standardsABSTRACT
BACKGROUND: No large evaluation has been performed of the maintenance vial concentration commonly used by physicians when prescribing imported fire ant (IFA) immunotherapy since the publication of the first Stinging Insect Hypersensitivity Practice Parameter 10 years ago. OBJECTIVE: To describe the prescribing patterns for IFA immunotherapy among practicing allergists in a large health care setting and the impact of published Practice Parameter recommendations. METHODS: Data from the US Army Centralized Allergen Extract Laboratory were analyzed to determine IFA immunotherapy prescribing patterns from 1990 to May 2007. This extract laboratory provides prescriptions for more than 320 US Department of Defense, US Department of Veterans Affairs, and US Public Health Service clinics. RESULTS: A total of 1,091 patients were given 1,437 new or revised prescriptions for IFA immunotherapy. Monotherapy for Solenopsis invicta and Solenopsis richteri was prescribed in 169 (11.8%) and 3 (0.1%) instances, respectively, with the remainder of patients given both IFA antigens. The most commonly prescribed maintenance vial dose was 0.5 mL of a 1:200 (wt/vol) dilution, accounting for 36.3% of prescriptions. A total of 17.3% of prescriptions had a maintenance vial dose of 0.5 mL of a 1:100 (wt/vol) dilution, 4.6% had a dilution of 1:10 (wt/vol), and 50.6% had a dilution between 1:10 and 1:100 (wt/vol). The mean starting dose was 4.4 10-fold dilutions below the maintenance dose (5.4 vials per treatment set). CONCLUSIONS: The most commonly prescribed maintenance dose was 0.5 mL of a 1:200 (wt/vol) dilution, although most prescriptions used a maintenance dose consistent with recommended dosing in the Stinging Insect Practice Parameters. Both IFA antigens were used by most physicians. Further study evaluating the effective dose range for IFA immunotherapy is needed.
