Consideration of which pharmacologic agent to use when a patient requires sedation prior to an oral surgery procedure entails a number of factors, including past medical history, current medications and dose level, duration of administration, pharmacologic interactions, and the dental needs of the patient. The case described in this report illustrates the importance of consideration of these factors in a patient who required sedation prior to oral surgery while taking 800 mg chlorpromazine, 300 mg amantadine hydrochloride, and 900 mg of cimetidine daily. The possible pharmacologic interactions which could occur from concomitantly administering either diazepam or a narcotic in the presence of these agents are numerous and significant. The choice of sedative agent was further complicated by the fact that the patient was prescribed chlorpromazine and amantadine in doses which far exceeded the usual therapeutic levels and had been maintained for an extended period of time, over 8 months. Consequently, any adverse reactions that may have resulted when sedating a patient taking chlorapromazine and amantadine hydrochloride in lower doses for a shorter duration would be more likely to occur with greater speed and severity in a patient receiving such high-dose, long-term therapy. Also, unusual reactions which have not been reported with usual therapeutic dose levels might also occur since these high doses approach toxic levels for some patients. Additionally, a sedative agent had to be used which would not interfere with the antipsychotic effects of chlorpromazine since the patient's psychiatric condition required maintenance of these unusually high therapeutic levels. The following case report gives the rationale and outcome of utilizing nalbuphine for obtunding pain and producing sedation during an oral surgery procedure under such complex therapeutic conditions.