The vitamins contained in Vitamin B-Complex capsule are completely non-toxic even in high doses and usually no effects occur. Sensitivity to Vitamin B1 however, may sometimes be encountered if administration is at prolonged intervals. Liver dysfunctions could also predispose patients to hypersensitivity reactions. Nevertheless, it must be stressed that hypersensitivity to Vitamin is very rare when orally given unlike if administered by intravenous injection where hypersensitivity is more often encounter.