Health effects of subacute treatment of combinations of gibberellic acid and ethephon (2-chloroethylphosphonic acid) were investigated. Mice was used as an experimental model. Ten groups of male ICR (CD-1) mice were treated with oral doses of 25, 50 and 100 mg of either gibberellic acid (GA3), ethephon (2-chloroethylphosphonic acid) alone or in combination / kg body weight for 11 weeks. A significant dose dependent reduction in weight gain and low dry matter intakes were recorded in animals treated with the combination of both chemicals. Treated groups showed statistically significant increases in mean liver, kidney and spleen weights. Hemoglobin (Hb) and total erythrocyte count (TEC) decreased while total leukocyte count (TLC) was raised in all treated groups. Gibberellic acid (alone) treated animals showed the highest activity of liver aspartate aminotransferase (AST) while no significant variations were recorded among other groups. No significant differences were recorded in the activity of hepatic alanine aminotransferase (ALT). A highly significant variation was recorded among the three treatments in serum urea level. No significant difference was noted among the three treatments in serum creatinine. All treatments caused significant dose dependent increases in creatinine than that of the control group. A highly significant dose dependent variation occurred in acetyl choline esterase (AChE) activity among treated groups. Groups treated with ethephon alone showed the greatest inhibition in brain AChE.