Oral Minoxidil vs Spironolactone

There is no licensed hair loss dose; this is the range in the dermatology literature. Prescribers start low, go up slowly, and stop where the balance is good.

Starting dose: Usually between a quarter of a milligram and 1.25 mg once a day, lower in women than men.

Going up: In small steps over weeks to months, guided by body hair, ankle swelling and blood pressure, not a schedule.

Usual dose: Broadly 1.25 mg to 2.5 mg a day in women, 2.5 mg to 5 mg in men, though plenty do well below that.

Total course: Open-ended. It works only while you take it.

Any time of day, with or without food, but the same time each day. Some take it at night because lightheadedness is easier lying down, especially in the first weeks and after a dose increase. Stand up slowly early on, and split tablets with a cutter rather than by hand.

Take it when you remember, unless the next one is close. Never double up. If you have missed several days, ask before restarting at your old dose — tolerance to the blood pressure effect fades.

Monitoring is clinical rather than laboratory. Blood pressure is checked at the start and after dose increases, and a doctor will ask at each review about ankle swelling, weight gain from fluid, breathlessness, palpitations and chest discomfort.

Routine ECGs, echocardiograms and blood tests are not standard for a healthy person on a low dose, but they may be requested for anyone with heart or kidney disease, and some prescribers want a cardiologist's opinion first. The high-dose label carries a boxed warning about fluid around the heart and worsening angina — described at doses far above the hair loss range, but the reason this drug is prescribed and reviewed rather than issued.

Weeks 1 to 4Starting: Nothing in the mirror. Lightheadedness on standing up quickly, if it happens, belongs here and usually settles. Ankles may feel tight by evening.

Weeks 2 to 8The early shed: Resting hairs are released so new ones can start, the same as with the topical. Expected, and it settles.

Months 1 to 3Extra hair: Fine hair appears on the face, arms or back in a good share of people. The price of the route, not a sign of trouble.

Months 3 to 6Regrowth: First scalp regrowth, usually at the crown and mid-scalp, fine at first and darkening later. Diffuse thinning in women is a common reason it is prescribed, with good reported response — though from case series, not placebo-controlled trials.

Months 6 to 12Judge it here: Density that has arrived by now tends to hold at a plateau while the dose continues.

Generic minoxidil tablets are inexpensive, and a 2.5 mg tablet split into quarters makes a month's supply cost very little.

Compounded low-dose liquid costs considerably more, because compounding is billed separately. Coverage varies and off-label use for hair loss often is not covered, so many people pay cash. A pill cutter is a few dollars and worth buying.