Can pumpkin seed oil be safely combined with other hair growth ingredients like minoxidil or biotin?

Hair loss is a concern that drives many to explore multiple interventions simultaneously. Among these, pumpkin seed oil (PSO), minoxidil, and biotin are often highlighted. To critically evaluate their combination, it is essential to understand not only their individual mechanisms but also the empirical evidence regarding their interaction and efficacy.

Pumpkin seed oil contains phytosterols, fatty acids, and antioxidants, which are thought to influence hair growth indirectly. The most cited mechanism is the potential inhibition of 5-alpha-reductase, the enzyme responsible for converting testosterone into dihydrotestosterone (DHT), a key factor in androgenetic alopecia. A clinical trial conducted in 2014 involved 76 men with mild to moderate androgenetic alopecia who received 400 mg of PSO daily for 24 weeks.

Hair counts and thickness were assessed using phototrichography and standardized photographs, revealing approximately a 40% increase in hair count compared to 10% in the placebo group. Hair thickness did not differ between the groups. The capsules were a branded product (Octa Sabal Plus) supplied by Dreamplus Co., Ltd., which also funded the study, and the trial did not measure DHT (Cho et al., 2014). The study was also small and included only men. One mouse study reported that topical PSO can counteract testosterone-induced hair growth suppression in mice over three weeks. The evaluation focused on the percentage of hair follicles in the anagen phase, a critical growth phase of hair follicles, which increased significantly compared to controls.

Minoxidil's Role in Hair Growth

Topical minoxidil's effect on hair growth has been shown in multiple trials, but how it works is not well understood. Animal and cell studies suggest it shortens the resting phase and may prolong the growth (anagen) phase; the ideas that it acts by opening potassium channels or by increasing blood flow have not been proven in the human scalp (Messenger & Rundegren, 2004). However, minoxidil’s effects are transient, and cessation often results in hair reverting to baseline within months. Biotin, a water-soluble B-vitamin, contributes to keratin synthesis. Yet, high-quality evidence for its effect on hair growth in non-deficient individuals is sparse. Most studies are anecdotal or involve small cohorts, suggesting benefit primarily in cases of actual deficiency. High-dose biotin can also distort some blood test results, including hormone tests (Li et al., 2017), so tell your doctor you take it before any blood test.

Evidence for Combination Therapies

The potential synergy between PSO and minoxidil has been explored, albeit in limited studies.

A 2025 trial randomized adults with androgenetic alopecia to receive a supplement containing pumpkin seed extract, Serenoa repens extract, and cysteine alongside 5% topical minoxidil for 24 weeks.

Its results could not be checked for this page: it is not indexed in PubMed, and the full report was not reviewed. Critically, the study combined multiple active compounds, making it difficult to isolate the effect of pumpkin seed extract alone. Furthermore, no high-quality trials have rigorously tested the combination of pure PSO, biotin, and minoxidil.

The evidence is hampered by small sample sizes, short durations, and variability in PSO formulations. Effects may differ based on concentration of phytosterols and fatty acids. While mechanistically plausible, these interventions’ combined efficacy cannot be conclusively stated. Biotin supplements appear to offer little benefit for people who are not deficient. Minoxidil remains the best-studied intervention, yet results are reversible upon discontinuation.

No study has tested whether pumpkin seed oil is safe or useful alongside minoxidil or biotin. Pumpkin seed oil is not an approved hair-loss treatment. If you use a hair-loss medicine such as minoxidil, ask a pharmacist or doctor before adding supplements. Biotin mainly helps people who are deficient, and it can affect some lab results.

References

Cho, Y. H., Lee, S. Y., Jeong, D. W., Choi, E. J., Kim, Y. J., Lee, J. G., Yi, Y. H., & Cha, H. S. (2014). Effect of pumpkin seed oil on hair growth in men with androgenetic alopecia: A randomized, double-blind, placebo-controlled trial. Evidence-based Complementary and Alternative Medicine, 2014, 549721. PMID 24864154. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4017725/

Li, D., Radulescu, A., Shrestha, R. T., Root, M., Karger, A. B., Killeen, A. A., et al. (2017). Association of biotin ingestion with performance of hormone and nonhormone assays in healthy adults. JAMA, 318(12), 1150–1160. https://pubmed.ncbi.nlm.nih.gov/28973622/

Hajhashemi, V., Rajabi, P., & Mardani, M. (2019). Beneficial effects of pumpkin seed oil as a topical hair growth-promoting agent in a mice model. Avicenna Journal of Phytomedicine, 9(6), 499-504. https://pdfs.semanticscholar.org/bf6a/d0addb0b607037be4b700d08324974cb90de.pdf

Messenger, A. G., & Rundegren, J. (2004). Minoxidil: Mechanisms of action on hair growth. British Journal of Dermatology, 150(2), 186-194. https://pubmed.ncbi.nlm.nih.gov/14996087/

Efficacy of oral supplementation with Serenoa repens, pumpkin seed extract and cysteine combined with topical minoxidil 5% vs topical minoxidil 5% alone in androgenic alopecia: A randomised assessor-blinded 6-month superiority trial. (2025). Clinical & Experimental Dermatology and Therapies. https://doi.org/10.29011/2575-8268.100233

Yelich, A. (2024). Biotin for hair loss: Teasing out the evidence. Journal of Clinical and Aesthetic Dermatology. https://jcadonline.com/biotin-for-hair-loss-evidence/