PubMed1988
Experimental data has shown that sodium valproate has analgesic properties in animals, probably by way of the increase in cerebral and spinal gamma amino-butyric acid (GABA) it induces. A study was therefore designed to assess this analgesia in man in the postoperative period. A first open study was carried out on 12 consenting patients, who were each given 15 mg.kg-1 sodium valproate intravenously over 20 min. A significant decrease in pain intensity, measured by an analogic visual scale, was seen from the 20th min up to the 140th min. A controlled double-blind study was then carried out; it included three groups of 13 patients each. Patients in group 1 were given placebo (5% dextrose); group 2 patients were given 15 mg.kg-1 sodium valproate intravenously over 20 min, and group 3 patients 2 mg.kg-1 ketoprofen intravenously over 20 min also. There was no difference in the pain intensity profile of groups 1 and 2: sodium valproate was no more efficient than placebo in relieving postoperative pain. However, ketoprofen gave a prompt and effective analgesic effect. The clinical data obtained with sodium valproate in man during the postoperative period stand in contrast with the promising animal results. Sodium valproate cannot be recommended for the treatment of postoperative pain.