Evaluation of oestrogenicity and pregnancy interceptory efficacy of lapachol (2-hydroxy-3-(3-methyl-2-butenyl)-1,4-naphthoquinone) in the mouse

Lapachol, a naphthoquinone isolated from Tectona grandis was evaluated for its oestrogenicity and antinidational activity in the mouse and was found to possess a statistically significant (p < 0.001) uterotrophic effect after administration of the drug at a dose of 20 mg/kg body weight/day/mouse, intramuscularly. However, in comparison with conjugated oestrogen, the drug proved to be a relatively weak oestrogenic. Lapachol when administered at the same dose level exhibited interceptory activity at all stages of early pregnancy.