Allergen extracts can degrade when exposed to temperatures beyond the optimum storage recommendation of 4 degrees C. Many allergen extracts are mailed to their final destinations throughout the year with exposure to varied environmental conditions.
Standardized timothy grass extracts, 10,000 and 100,000 BAU/mL, were mailed round-trip between San Antonio, Texas, and Phoenix, Arizona, during August 2007. In-transit temperatures were recorded using a temperature logger. Measured extract exposure temperatures were greater than 20 degrees C for 11 days and 30 degrees C for 6 hours during standard mailing in weather temperatures exceeding 38 degrees C.
After mailing of the extracts, the researchers performed in vitro enzyme-linked immunosorbent assay inhibition and in vivo ID50 EAL (Intradermal Dilution for 50-mm Sum of Erythema Determines Bioequivalent Allergy Units) analysis.
These were not statistically significant differences on either test.
Mailing of timothy grass extract produced no significant reductions in in vitro relative potencies or in vivo skin test reactivity in 3 sensitive patients.
Pollen-producing plants (weeds and trees). V. Dimov, M.D.
Effects of summer mailing on in vivo and in vitro relative potencies of standardized timothy grass extract. Moore M, Tucker M, Grier T, Quinn J. Ann Allergy Asthma Immunol. 2010 Feb;104(2):147-51.