Epidural Met‐Enkephalin (FK 33–824). A Dose‐Effect Study

The present study examines the analgesic effect on postoperative pain of 0.001‐0.5 mg of epidural FK 33–824. a synthetic met‐enkephalin analogue. The results showed that FK 33–824 diluted in 10 ml of isotonic aalinr induced analgesia in doses of 0.02, 0.05, 0.1, 0.2, and 0.5 mg. The analgesic effect, however, was inferior to that of epidural morphine (4 mg in 10 ml isotonic saline), since analgesia was unpredictable and clinically insufficient in four out of eight patients receiving 0.02‐0.5 rng. Additionally, the duration of action was shorter for FK 33–824 than for morphine.