An Exploratory Preclinical In Vivo Pilot Study Evaluating the Hair Growth–Promoting Effects of <i>Rosmarinus officinalis</i> and <i>Ricinus communis</i> Combination

This preclinical in vivo pilot study evaluated the hair growth-promoting effects of a combination of Rosmarinus officinalis and Ricinus communis oils in mice. Fifteen mice were divided into five groups, including a combination group, rosemary oil, castor oil, 2% minoxidil (positive control), and untreated (negative control). After 28 days of topical treatment, the combination group showed a higher mean hair length (12.88 ± 0.79 mm) compared to individual oils and similar trends to 2% minoxidil (13.06 ± 0.21 mm). Although the results suggest potential hair growth benefits, the findings are based on a murine model and cannot be directly applied to humans.