Average weight gain with time. The bar chart showed average weight of rats per group at days 0, 7, 14 and 21 of sub-acute toxicity study. There is an obvious increase in the animal's weight; it is shown to be continuous in the four treatment groups as well as the vehicle control. Zinc-aluminium levodopa nanocomposite high dose (ZALH 500 mg/kg), zinc-aluminium levodopa nanocomposite low dose (ZALL 5 mg/kg), zinc-aluminium nanocomposite high dose (ZAH 500 mg/kg), zinc-aluminium nanocomposite low dose (ZAL 5 mg/kg), vehicle control (VC normal saline 100 ml/kg body weight). There is statistically significant difference (#) between day 0 and all other days in all the groups (p < 0.05). One-way ANOVA was used, and data are expressed as means ± SD.