Double-blind placebo controlled specific immunotherapy with mixed Cupressaceae taxodiaceae pollens in respiratory allergy to Cupressus sempervirens.

Twenty adult patients presenting a respiratory allergy to the pollen of Cupressus sempervirens were randomly divided into two groups; one received a placebo the other one an equal mixture of Cupresssus sempervirens and Cryptomeria japonica pollen during a period of 3 years (1993-1996). According to the following criteria: symptoms score, drug consumption, skin test and RAST, nasal provocation test, the results for the treated group were statistically better than those for the placebo group. No side effects were observed.