<p>If there is no history of previous serum injection or allergic reaction, the dose of serum may be given intramuscularly. If the patient is subject to allergic diseases, a trial dose of 0,2 ml (diluted 1:10 if preferred) of the serum should be given subcutaneously; if no general reaction develops during an interval of 30 minutes, the main dose may be given intramuscularly. The patient must be kept under observation for at least 30 minutes after the injection and adrenaline kept in readiness for emergency use. In all urgent cases, the intravenous route is indicated, but should never be used unless a preliminary intramuscular injection, given at least 30 minutes beforehand, has been tolerated. For intravenous use, the serum should be at room temperature, the injection should be given very slowly, and the patient should be recumbent during the injection, and for at least an hour afterwards.</p>