<p>Vancomycin is well tolerated. However during or soon after rapid infusion of Vancomycin, patients may develop anaphylactic reactions including hypotension, wheezing, dyspnoea, urticaria or pruritus. Rapid infusion may also cause flushing of the upper body (&quot;red neck&quot;) or pain and muscle spasm of the chest and back. These reactions usually resolve within 20 minutes but may persist for several hours. Such events are infrequent if Vancomycin is given by a slow infusion over 60 minutes.</p>