Injections are administered on a first come, first served basis. We ask that you take an antihistamine prior to receiving your injections to aid in eliminating any chance of a reaction to the injections. Experience has shown that the majority of reactions, which require emergency treatment, occur within 30 minutes of an injection. It is for this reason that all patients who receive such injections must remain for 30 minutes in our designated waiting area until checked by one of our clinic nurses. Anyone leaving prior to this time does so against medical advice and a repeat offender may be prevented from receiving allergy shots.