Background and objective: To compare the efficacy of tramadol and ondansetron in minimizing the pain due to injection of propofol in 100 patients.

Methods: An intravenous cannula was inserted in the dorsum of the hand. After tourniquet application to the forearm, tramadol 50 mg (Group 1, n = 50) or ondansetron 4 mg (Group 2, n = 50) was injected. The tourniquet was released after 20 s, and propofol 5 mL was administered over 5 s. The patients were observed and asked if they had pain in the arm and the response was assessed. Nausea and vomiting and degree of sedation were recorded for the first postoperative 24 h.

Results: Twenty-one patients in Group 1 and 14 patients in Group 2 reported no pain. Slight pain was seen in 15 patients in Group 1 and in 18 patients in Group 2. Moderate pain was seen in 10 patients in Group 1 and 15 patients in Group 2. Severe pain was seen in four of the patients in Group 1 and three patients in Group 2. There was no significant difference of pain between Groups 1 and 2, but we found a significant reduction of nausea and vomiting in the ondansetron group compared with the tramadol group (P = 0.033).

Conclusions: Tramadol or ondansetron are equally effective in preventing pain from propofol injection. The added benefit of a reduction in nausea and vomiting after operation in the ondansetron group may be a reason to prefer this drug.