The most effective options for hair loss depend on the cause, but for the most common type (pattern hair loss), three FDA-approved treatments have the strongest evidence: topical minoxidil, oral finasteride, and low-level light therapy. Beyond those, nutritional deficiencies, scalp care, and newer procedures like platelet-rich plasma injections can all play a role. Here’s what actually works, how well it works, and what to expect.
Minoxidil: The Over-the-Counter Standard
Minoxidil is available without a prescription in liquid and foam forms. It works by increasing blood flow to hair follicles and extending the growth phase of each hair. You apply it directly to thinning areas of the scalp, typically twice a day.
The two main concentrations are 2% and 5%. In a 48-week clinical trial, the 5% version produced 45% more hair regrowth than the 2% version. People using the stronger concentration also saw results earlier. The tradeoff is a higher chance of scalp itching and irritation with the 5% formula, though both concentrations were well tolerated overall with no systemic side effects. Minoxidil is approved for both men and women.
One important detail: minoxidil only works while you use it. Stop applying it and new growth gradually falls out over a few months. Most people see visible improvement around the three to six month mark, so patience matters early on.
Finasteride: Prescription Hormone Blocker
Pattern hair loss in men is driven largely by a hormone called DHT, which is made when an enzyme converts testosterone into a more potent form. DHT shrinks hair follicles over time until they stop producing visible hair. Finasteride blocks that enzyme, reducing DHT levels and slowing or reversing miniaturization of the follicle.
The standard dose for male pattern hair loss is 1 mg daily, taken as a pill. It has been approved for this purpose since 1997 and remains one of the most studied hair loss treatments available. Finasteride is not approved for women and is classified as dangerous during pregnancy because it can cause birth defects in male fetuses.
Many dermatologists recommend combining finasteride with minoxidil, since they work through different mechanisms. Finasteride addresses the hormonal root cause while minoxidil stimulates growth directly.
Low-Level Light Therapy
Light therapy devices, often sold as helmets or caps you wear at home, use red and near-infrared light to stimulate hair follicle cells. The wavelengths that show the most promise in clinical research range from 630 to 970 nanometers. In one 24-week trial, participants used a helmet-shaped device for 20 minutes daily and saw measurable improvements in scalp condition and hair growth.
Light therapy is FDA-cleared as a treatment for pattern hair loss and is considered safe with virtually no side effects. It tends to produce more modest results than minoxidil or finasteride on its own, which is why it’s often used as an add-on rather than a standalone treatment.
Nutritional Deficiencies That Thin Your Hair
Before starting any topical or prescription treatment, it’s worth checking whether a nutritional gap is contributing to your hair loss. Two deficiencies stand out in the research: iron and vitamin D.
Iron and Ferritin
Ferritin is the protein that stores iron in your body, and your hair follicles are sensitive to low levels. Research shows optimal hair growth occurs when serum ferritin reaches about 70 ng/mL. Even treatments targeting hormonal hair loss work better when ferritin levels are adequate. One study found that anti-androgen therapy had better outcomes when ferritin was above 40 ng/mL. Many women with unexplained hair thinning turn out to have low ferritin, sometimes even when their standard iron blood test looks normal.
Vitamin D
In a study comparing people with diffuse hair loss to healthy controls, nearly 80% of the hair loss group had low vitamin D levels, with an average reading of just 14 ng/mL. The normal range is 20 to 70 ng/mL. Vitamin D plays a role in the hair follicle growth cycle, and correcting a deficiency through supplementation or sun exposure may help reduce shedding. A simple blood test can tell you where you stand on both ferritin and vitamin D.
Vitamin B12 also supports healthy hair growth, with optimal levels falling between 300 and 1,000 ng/L.
Saw Palmetto as a Natural Option
Saw palmetto is a plant extract that works similarly to finasteride by partially blocking the conversion of testosterone to DHT, though it’s far less potent. Clinical trials have used doses between 100 and 320 mg daily, and several randomized studies show positive effects for people with mild to moderate pattern hair loss. The extract is primarily made up of fatty acids (70 to 95%) along with plant sterols that contribute to its anti-androgen activity.
Saw palmetto is not a replacement for finasteride if you’re experiencing significant hair loss, but it may be worth trying if you prefer a supplement-first approach or want to avoid prescription side effects. Results are typically more subtle and take longer to appear.
Platelet-Rich Plasma (PRP) Injections
PRP involves drawing a small amount of your blood, spinning it to concentrate the platelets and growth factors, then injecting that concentrate into thinning areas of your scalp. The growth factors are thought to wake up dormant follicles and extend the active growth phase of hair.
The most common protocol is three treatment sessions spaced one month apart, followed by booster sessions every six months. There is no single standardized schedule, and results vary. PRP is not FDA-approved specifically for hair loss, but it’s widely offered by dermatologists and hair restoration clinics. The cost adds up since treatments need to be repeated indefinitely to maintain results.
Scalp Massage
Daily scalp massage is one of the simplest things you can try. In a small study, men who massaged their scalps for just 4 minutes a day saw a statistically significant increase in hair thickness after 24 weeks. Hair diameter went from an average of 0.085 mm to 0.092 mm. The researchers found that the stretching forces from massage stimulate cells at the base of the hair follicle. Results were already measurable by 12 weeks.
Scalp massage won’t reverse advanced hair loss on its own, but it costs nothing and may complement other treatments by improving blood flow and follicle health.
Matching Treatment to Your Type of Hair Loss
Not all hair loss responds to the same treatments. Pattern hair loss, the most common type in both men and women, is driven by genetics and hormones. It follows a predictable progression. In men, it typically starts with a receding hairline at the temples and can advance through stages, from minor recession to significant thinning across the top of the scalp. Pattern hair loss responds best to minoxidil, finasteride, and DHT-blocking approaches.
Diffuse hair shedding, where hair falls out evenly across the scalp, is more commonly linked to nutritional deficiencies, stress, thyroid problems, or hormonal shifts after pregnancy. In these cases, treating the underlying cause is more important than applying topical solutions. Temporary shedding from stress or illness, called telogen effluvium, typically resolves on its own within six to nine months once the trigger is removed.
If your hair loss appeared suddenly, is patchy, or comes with scalp pain or scarring, the cause may be something other than pattern hair loss, and the treatment path will be different. Getting clarity on the type of hair loss you’re dealing with is the single most useful step before committing to a treatment plan.