The science ofRE:YOU

Minoxidil is a vasodilator originally developed to lower blood pressure. In hair follicles, it is thought to support growth by improving local blood flow, but because it still affects vascular activity and can irritate of spread beyond the scalp, side effects may include shedding, itching, flaking, unwanted facial or body hair, dizziness, swelling and cardiovascular issues.

Finasteride was originally used to treat benign prostatic hyperplasia and was later found to help slow androgen-driven follicle miniaturization. However, since it affects hormone signaling, possible side effects include reduced libido, sexual dysfunction, and mood changes, including depression. Finasteride is not FDA-approved for use in women and should not be used during pregnancy, as exposure may pose a risk to a developing male fetus.

Hair-growth supplements are designed to support hair from within, but their effects depend on digestion, absorption, baseline nutrient status, and whether the body actually needs the vitamins or minerals. Effects may include nausea, bloating, stomach discomfort, diarrhea and medication interactions.

Cosmetic hair serums may improve scalp feel and make hair appear healthier, but many rely on botanical ingredients, conditioning agents, and cosmetic claims rather than proprietary actives with strong evidence for targeting the follicle and its surrounding environment. Evidence is often limited, and differences in formula stability or scalp penetration can make results inconsistent. Side effects may include irritation, itching, flaking, sensitivity, or contact dermatitis.