The effect of a 3-week treatment with Loderix is examined in an open study in 40 patients suffering from allergic rhinoconjunctivitis. Side-effects, mainly sleepiness, fatigue, weakness, were observed in nearly half of the patients. These were, in general, mild and of a transient character. Treatment had to be stopped in 2 patients due to developed adverse effects. Safety parameters as blood picture, liver function tests, renal function parameters showed no alterations during the study course. During the treatment periods rhinoconjunctivitis symptoms disappeared or significantly decreased in 22 patients out of 40. Moderate effect was registered in 14 patients, and treatment was ineffective in 4 cases. In 6 patients the doses were doubled from the 2nd week of treatment causing an increase in effectivity without a change in side-effect profile.