No acute toxicological effects have resulted from studies involving megestrol acetate administered in dosages as high as 1600 mg/day for six months or more. Reports of overdose have been received in the postmarketing setting. Signs and symptoms reported in the context of overdose included diarrhoea, nausea, abdominal pain, shortness of breath, cough, unsteady gait, listlessness, and chest pain. There is no specific antidote for overdose with Giga. In case of overdose, appropriate supportive measures should be taken.