Carbamazepine is effective in the treatment of 21-day-old Wistar rats injected with Tityus serrulatus crude venom

The scorpion-envenoming syndrome has an incidence of approximately 8000 accidents/year in Brazil; with most severe cases occurring during childhood and elderly. Previous results from our laboratory suggest that the effects of scorpion toxins on the central nervous system play a major role on the lethality induced by scorpion envenoming. Our group has shown that the pre-treatment with carbamazepine (CBZ) is able to increase the latency-to-death in developing animals inoculated with tityustoxin, a toxic fraction of the Tityus serrulatus crude venom. Nevertheless, in order to perceive CBZ as potentially useful in clinical practice, the efficiency of CBZ against crude venom inoculation and the pharmacological treatment introduced after envenomation must be addressed. Thus, the objective of this work was to evaluate CBZ therapeutic efficiency against scorpion envenomation in developing rats. Animals were treated with i.p. injections of either vehicle or CBZ (50 mg/kg or 100 mg/kg) 10 min after injected with a s.c. fixed volume of either saline or crude T. serrulatus venom extract (48 mg/kg). The dose chosen for venom inoculation was 16 times its DL50 for 21-day-old Wistar rats, invariably inducing death within 2 h. Although CBZ did not significantly reduce the pulmonary edema, it was effective in increasing survival rate by approximately 75% in treated rats. In conclusion, CBZ was effective in the treatment of T. serrulatus envenomation even though not blocking the pulmonary edema.