Systemic adrenaline attenuates skin response to antigen and histamine.

Six atopic subjects received either adrenaline (0.3 ml of 1 mg/ml), subcutaneously over the deltoid muscle, or saline on 2 separate days. After 10 min, histamine and antigen were injected intradermally in the forearm. Adrenaline significantly inhibited the flare of histamine and both the flare and weal of antigen (P less than 0.05). This anti-allergic action of adrenaline occurred with a dose that we have previously shown produces plasma concentrations at the upper limit of the physiological range in resting normal subjects.