Toxicological Studies on Procyanidin B-2 for Extern?al Application as a Hair Growing Agent

In 1999, researchers conducted toxicological tests on procyanidin B-2, a plant-derived compound, to assess its safety as a topical hair growth agent. The tests included mutagenicity assessments with bacteria and mice, chromosomal tests with CHL cells, acute toxicity via subcutaneous injections in rats, skin and eye irritation tests with rabbits, and skin sensitization tests with guinea pigs. The results indicated that procyanidin B-2 was non-mutagenic, did not cause chromosomal aberrations except for polyploidy, and was not toxic at doses up to 2000 mg/kg. It also did not cause significant skin or eye irritation or skin sensitization. These findings led to the conclusion that procyanidin B-2 is safe for external use as a hair growth agent. The number of animals used in each test was not specified in the summary.