This product is formulated using a special two-stage, timed-release concept. The two-stage ingredients are designed so that half are intended to be rapidly released while the other half are intended to be gradually released over 6-8 hours. The two-stage ingredients in Solaray Mega B-Stress include Vitamin C, Thiamine, Riboflavin, Niacinamide and Vitamin B-6.

Source: Solaray