Douglas Laboratories has been a trusted name in professional-grade nutritional supplementation since 1955, making it one of the longest-standing supplement manufacturers in the United States. Based in Pittsburgh, Pennsylvania, Douglas Labs operates a state-of-the-art, NSF GMP-certified manufacturing facility with rigorous in-house quality control at every production stage. Their product catalog spans over 800 formulas — from foundational vitamins and minerals to specialized clinical formulas for practitioners. Douglas Laboratories formulates using the most bioavailable nutrient forms available: Albion-chelated minerals, methyl-B vitamins, and patented specialty compounds. For those who want practitioner-quality nutrition without a prescription, Douglas Laboratories is the benchmark brand.