To compare the analgesic and side effects of post-operative analgesia between epidural administration ofneostigmine (NEO) and morphine (MOR) or their combination in patients undergoing abdominal surgery. Methods: One hundredand two selective patients undergoing surgery were randomly divided into five groups at the end of the surgical procedure. GroupN1 (n=11) and Group N2(n =15) were administered epidurally with NEO 1 mg and 2 mg respectively, Group M1 (n=18)and Group M2 (n=55) were administered epidurally with MOR 1 mg and 2 mg respectively, Group M1 + N1 (n=17) was administered epidurally with the combination of MOR 1 mg and NEO 1 mg. Results: Single dose epidural administration of NEO (1mg and 2 mg) or MOR (1 mg and 2 mg) showed dose-dependent analgesic effects. The analgesic duration in Group N1 (4.7 ± 2.7 h) was significantly shorter than other four groups (P<0. 01). Group M1, M2 and M1 + N1 showed better analgesic effectsthan group N1 and N2 (16.1±8.7h) , with similar analgesic durations in Group M1, M2 and M1 + N1. me percentages of excellent, good and poor effects were 0%, 54.5 % and 45.5 % respectively in Group N1. The percentages of excellent and good effects were 100% in Group M2 and M1 + N1, but 83.3% in Group N2. The time to first use analgesic medication was similar inGroup M1, M2 and M1 + N1, but longer compared with Croup N1 and N2. The incidences of nausea and vomiting closelyresem-bled one another in Croup N1, N2 and M1 + N1, which were less than those in Group M1 and M2. The incidence of urinary retention was 51.2%, 25.0% and 31.3% in Group M2, M1 and M1 + N1, respectively, but 0% in Group N1 and N2. In GroupN2 two patients opened the bowel movement and one patient developed bradycardia (58 beats/min) at 45 min after receiving NEO.Conclusion: Epidural administration of NEO produces dose-dependent prolonged analgesic effects (similar to MOR) and the combination of MOR and NEO could produce analgesia with fewer side effects than administration of equivalent analgesic doses of eachdrug separately. me epidural administration of NEO 2 mg could provide satisfactory postoperative analgesia.
