[Histamine levels in blood of patients with allergic bronchial asthma (author's transl)].

The investigation of 10 patients with allergic asthma showed histamine levels of 79.8 +/- 50.0 ng/ml in blood during symptom-free intervals. They were not significantly different from those in 12 patients with chronic obstructive bronchitis (54.0 +/- 25.9 ng/ml) and in 13 healthy probands (56.9 +/- 21.5 ng/ml). It could be shown that allergen-induced bronchial obstruction in patients with allergic asthma had no demonstrable influence on blood histamine levels. The absence of increased blood histamine levels in allergic bronchial obstruction supports the assumption that allergen-induced liberation of histamine and its biological effects are mainly limited to the bronchial system. Local metabolisation of the liberated mediator can be supposed to a large extent.