Finasteride

What finasteride is, and who the US label actually covers

Finasteride is a prescription tablet that blocks an enzyme called 5-alpha reductase and lowers a hormone called DHT (dihydrotestosterone). US labeling approves it for male pattern hair loss in men only, plus a higher strength for an enlarged prostate. It is not approved for women or for children.

That is the whole drug in four sentences. The longer version matters because this medicine is bought online more often than almost any other men’s health prescription, and the marketing around it is far less careful than the label. The drug class is 5-alpha reductase inhibitor. The route is oral. The product type is human prescription drug, so a licensed clinician has to authorize it, whether you see that clinician in a clinic or through a telemedicine intake.

Two approved strengths exist in the United States. The 1 mg tablet is the labeled option for male pattern hair loss, also called androgenetic alopecia, and was sold under the brand name Propecia. The 5 mg tablet is labeled for benign prostatic hyperplasia (BPH), an enlarged prostate that makes urinating slow or frequent, and was sold as Proscar. Both are now widely available as generics from multiple manufacturers. For a plain description of the labeled uses and daily tablet schedule, see the MedlinePlus entry for this medication.

The label also draws a line that most advertising skips. Effectiveness in bitemporal recession, meaning the receding corners at the temples, has not been established. The studied benefit sits at the crown and mid scalp. If your main concern is a receding hairline, that is worth raising with a clinician before you start, not after six months of hoping. You can see how this compares with other treatments in our Medication Reference Index.

How it works on DHT, and how long anything takes

Male pattern hair loss is largely driven by DHT, a potent androgen your body makes from testosterone. In people with a genetic sensitivity to it, DHT gradually shrinks scalp follicles. Each growth cycle produces a finer, shorter, weaker hair until the follicle stops producing a visible one at all. That process is called miniaturization.

This drug inhibits the type II form of 5-alpha reductase, the enzyme that converts testosterone into DHT. Less enzyme activity means less circulating DHT. Published pharmacology summaries put the reduction in serum DHT at roughly 70% at the 1 mg dose, and a clinical review of the drug’s pharmacology is available in the StatPearls monograph hosted by the NCBI Bookshelf. Testosterone itself is not blocked, which is why this is not testosterone suppression therapy.

Three practical points follow from the mechanism. First, the drug works upstream of the follicle, so it protects follicles that are still alive and shrinking. It does not raise the dead. Areas that have been completely bald for years are unlikely to respond. Second, hair grows slowly, so nothing visible happens quickly. The pivotal trials measured change at 12 months, and patient-facing guidance from major clinics generally suggests giving it several months before judging anything. A useful summary of expected timelines sits in the Cleveland Clinic page on this tablet for alopecia. Third, the effect is maintenance, not cure. When the drug stops, DHT returns to baseline and the hair gained is generally lost over the following months. That is the single most important fact for anyone doing the math on cost: this is a subscription to a hormone effect, not a course of treatment.

Some men also notice more shedding in the first weeks. That is commonly described as a normal part of follicles resetting their cycle, but any sudden or patchy loss deserves a clinical look rather than a guess.

Approved tablets, brand versus generic, and the compounded topical question

Generic tablets and the original brand contain the same active ingredient and go through FDA review for bioequivalence, meaning the generic has to deliver the drug to the bloodstream in the same way. Approval records for both are searchable in the Drugs@FDA database of approved products. In practice, price is usually the only meaningful difference between the brand and a generic tablet of the same strength.

Topical versions are a different regulatory animal, and the difference is not cosmetic.

Compounded medicines are mixed by a pharmacy for an individual patient or, at larger scale, as an outsourcing facility batch. A 503A pharmacy compounds patient-specific prescriptions. A 503B outsourcing facility registers with the FDA and can produce larger batches under stricter manufacturing expectations. Neither route means the finished product was reviewed for safety, effectiveness or quality before it went on sale. Some absorption into the bloodstream still occurs with topical use, so the systemic warnings below are not automatically erased by putting the drug on your scalp instead of your tongue. If a program offers a topical, ask which pharmacy compounds it, at what strength, and what the vehicle is.

Side effects, from the common ones to the ones that make headlines

The honest answer to what the biggest side effect is: sexual side effects. In the year-one pivotal trials at the hair loss strength, decreased libido, erectile difficulty and problems with ejaculation were each reported by under 2% of men, roughly half a point to one point above placebo. Small numbers, but real ones, and they are the reason most men who quit, quit.

Reported effects generally cluster like this:

• Sexual: lower libido, erectile difficulty, reduced ejaculate volume or trouble ejaculating.
• Breast tissue: tenderness, swelling or enlargement, sometimes on one side only.
• Skin and allergy: rash, itching, hives, and less commonly swelling of the lips, face or throat.
• Mood: reports of depressed mood, depression and suicidal thoughts appear in current labeling and regulatory reviews.
• Other: testicular pain, dizziness, weakness or headache.

In the trials, sexual side effects resolved in most men who stopped the drug, and in a portion of men who stayed on it. The harder question is whether they can persist. Labeling for this class acknowledges reports of continued erectile dysfunction, low libido and ejaculation problems after discontinuation, along with reports of male breast cancer. How often that happens, and how much of it the drug causes, is genuinely unsettled in the literature. Adverse event reports and labeling changes for this molecule are tracked through the FDA’s drug safety and availability updates. A calm reading is that persistent effects appear to be uncommon, are taken seriously enough to sit in official labeling, and are not something a marketing page should wave away. A general clinical summary of the side effect profile is also set out in the Mayo Clinic drug entry for the oral route.

Fertility is a separate conversation. Reduced ejaculate volume is documented, and effects on sperm parameters have been reported in some men. If you and a partner are trying to conceive, raise it before you start.

Warnings that change what you do, not just what you read

Three warnings on this label have practical consequences.

Pregnancy and tablet handling. The drug can harm a developing male fetus. Labeling instructs that women who are pregnant or may become pregnant should not handle crushed or broken tablets. Whole tablets are coated for that reason, so pill splitting is not a neutral cost hack in a household where someone could be pregnant. Coated tablets and separate storage are simple ways to respect that warning.

PSA and prostate screening. This medicine lowers prostate specific antigen (PSA), the blood marker used in prostate cancer screening, by roughly half. That does not hide cancer if the person reading the result knows you are taking the drug, because clinicians interpret PSA differently for men on a 5-alpha reductase inhibitor. It does mean any confirmed rise in PSA while on treatment deserves evaluation, even if the number still looks normal for an untreated man. Tell every clinician who orders a PSA that you take this drug. Background on prostate conditions and testing is available from the NIDDK’s patient information on prostate problems.

High-grade prostate cancer labeling. Labeling for drugs in this class notes an association with an increased risk of being diagnosed with high-grade prostate cancer, based on prevention trial data. Overall prostate cancer diagnoses were lower in those trials. This is a nuanced trade-off, not a reason to panic, and it belongs in a conversation with a clinician who knows your age, family history and screening plan.

The drug is also not indicated for women or pediatric patients, and use is contraindicated in anyone with a known hypersensitivity to it.

Interactions and what to disclose before the first tablet

Compared with most prescriptions, this one has a short interaction list. It is processed by the liver enzyme CYP3A4, but clinically important interactions are considered uncommon, and routine dose changes for other medicines are not standard. That is a genuine advantage of the molecule, and it is one reason asynchronous telehealth intakes handle it comfortably.

Short list still means not empty. Things worth putting on the intake form or saying out loud:

• Any other 5-alpha reductase inhibitor, including dutasteride, since stacking them adds risk without a labeled reason.
• Liver disease or abnormal liver tests, since the liver clears this drug.
• Any history of depression, anxiety or suicidal thoughts.
• Prostate symptoms, prior PSA results, or a family history of prostate cancer.
• Plans to conceive, or a partner who is pregnant or may become pregnant.
• Supplements marketed for hair or prostate health, including saw palmetto, which acts on the same pathway and can muddy the picture.
• Breast lumps, tenderness or nipple discharge, before or during treatment.

Interaction and precaution details for consumers are laid out in the UK NHS medicines page on this tablet, which is useful plain-language reading even though US labeling governs American prescriptions. For related molecules and how they differ, our Independent Editorial Analysis section covers the men’s health category in more depth.

How telehealth programs handle this prescription, and what varies

Hair loss is close to an ideal telehealth condition: the diagnosis is often visual and pattern-based, no lab work is routinely required by the label, and the tablet is cheap generically. That is why so many programs offer it. What differs between them is not the molecule. It is everything around it.

1. Consult model. Some programs run a questionnaire reviewed asynchronously by a clinician. Others include a live video visit. Both are legal where the prescriber holds a license in your state, which is the constraint that decides availability more than anything else.
2. Prescriber disclosure. Whether you can see who wrote the prescription, and whether you can message that person later, varies a lot.
3. Pharmacy fulfillment. A prescription may be sent to your local pharmacy, filled by a mail-order partner, or, for topicals, produced by a compounding pharmacy. Legitimacy of online pharmacy operations can be checked through LegitScript’s certification lookup for online pharmacies.
4. What the monthly charge buys. Some prices are medication only. Others bundle a membership, clinician messaging, shipping or a second product such as topical minoxidil.
5. Renewal and cancellation. Introductory pricing that steps up at month two or four is common. So are quarterly shipments billed as one charge.

Programs offering this molecule are listed on this page automatically, and the patient ratings and scored dimensions behind each one are explained in How Patient Scores Work. Reviews on the site are moderated. If you want to compare the wider men’s health field first, start with the Telehealth Provider Directory.

What a month costs when you pay cash

Cost is the reason most people scroll to the bottom of a page like this, so here it is on a single basis: US dollars per month, self-pay, no insurance involved. Across the programs tracked here, the lowest recurring self-pay price for this medication is $10 a month, the median sits at $25, and the top of the tracked range reaches $109. That spread of $99 across 5 tracked programs is the story: same active ingredient, very different bills. Advertised self-pay prices move often, so treat any figure as a snapshot rather than a fixed rate.

What actually moves the number:

• Brand versus generic. Generic tablets are the cheap end. Brand-name pricing is a different tier for the same molecule.
• Tablet strength and quantity. The prostate strength and the hair loss strength are priced separately, and a 90-day supply usually costs less per month than monthly billing.
• Oral versus compounded topical. Compounded topicals and combination formulas generally cost more than a generic tablet, because a pharmacy is making them to order.
• Bundling. A price that includes shipping, clinician access and a second product is not comparable to a bare medication price.
• Intro versus renewal. The first-month figure in an ad is frequently not the ongoing one.

Because this is long-term maintenance, the monthly figure matters less than the annual one. Run your own numbers before you commit:

More cost tools sit in our Free Health Calculators collection, and a worked example of how program costs are compared side by side is in the Free Savings Report.

On insurance: never assume. Plans commonly treat treatment for pattern hair loss as cosmetic and exclude it, while the same molecule prescribed for an enlarged prostate is more often billable. Whether a plan pays is decided by your specific formulary and plan documents, not by a website, so verify with your own plan before you count on it. For broader context on how drug benefits and out-of-pocket costs are structured, KFF publishes ongoing research on prescription drug costs. Many people using cash-pay telehealth for this drug are doing so precisely because it is cheaper than a claim and a copay.

Comparing it with minoxidil, dutasteride and spironolactone

These four drugs get mentioned in the same breath and do genuinely different things.

Minoxidil does not touch DHT. Applied to the scalp, it acts on the follicle and its blood supply, prolonging the growth phase. Topical minoxidil is approved over the counter for pattern hair loss in both men and women, which makes it the easiest starting point for many people. Oral minoxidil is prescribed off-label for hair loss and is a blood pressure medication by approval. Because the mechanisms differ, clinicians frequently use a DHT blocker and a topical together rather than choosing between them. Our page on Minoxidil For Hair Regrowth covers that pairing.

Dutasteride inhibits both type I and type II 5-alpha reductase, so it lowers DHT more completely. In the United States it is approved for BPH, not for hair loss, so hair loss use is off-label. It also has a much longer half-life, which means side effects and washout take longer to resolve. Read the trade-offs in How Dutasteride Compares.

Spironolactone is an anti-androgen used off-label for female pattern hair loss. It is a common comparison because the DHT blocker on this page is not indicated for women, and labeling is explicit that women should not use it, with an additional handling warning during pregnancy. Some clinicians do prescribe 5-alpha reductase inhibitors off-label to postmenopausal patients, but that is a specialist decision with a thinner evidence base and clear reproductive-safety boundaries, not a routine online purchase. Our page on Spironolactone For Female Hair Thinning sets out how that option is used.

Topical versus oral comes down to what you are trying to avoid. The appeal of a topical is lower systemic exposure and, in theory, fewer sexual side effects. The catch is that US topicals are compounded rather than approved, absorption varies, and the comparison data is limited.

What to ask a clinician, and when to seek care

Bring these to a consult, whether it happens in an office or through an intake form:

• Is my pattern of loss the type that has been studied for this drug, or is it mostly temple recession?
• What would make you tell me to stop, and how do I reach you if something changes?
• How will my PSA testing be handled, and at what age should that start?
• What happens if I stop after a year, and what is the plan then?
• Is the product an approved tablet or a compounded preparation, and which pharmacy fills it?
• Does the monthly charge include the medication, clinician acc