Patient Handout – Minoxidil (Rogaine)

Minoxidil promotes hair growth by lengthening the growth phase of hair follicles and causing more follicles to produce hair. The hairs that are produced tend to be larger and thicker. Minoxidil is available in a 2 and 5 percent liquid or 5 percent foam. The 5 percent solution is more effective in men and is probably more effective in women. It can be purchased without a prescription.

How to apply

Minoxidil is a scalp treatment, not a hair treatment. One milliliter of the liquid or foam should be applied to the affected areas of the scalp using a dropper or pump spray device. The solution should be lightly spread over the affected area with a finger. People using minoxidil must have a normal, healthy scalp
since cuts or openings can allow the solution to be absorbed into the bloodstream.


Minoxidil must be used for at least six months to determine if it is effective. When it is effective, you usually begin to shed less hair within two months after the start of treatment, and by four to eight months hair begins to grow. The effects of minoxidil usually stabilize after 12 to 18 months of use.

Treatment with minoxidil must be continued indefinitely. If it is discontinued, any hair that has been maintained or regrown as a result of the medication will be lost.

Not all people benefit from minoxidil. The best results are seen when baldness has been present for less than five years, when it affects the crown (top) of the head, and when the area of hair loss is less than 10 centimeters in diameter. Studies have shown that 30 to 40 percent of men and women with crown
hair loss experience cosmetically significant results with minoxidil.

Side effects

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call us or get medical help if any of these side effects or any other side effects bother you or do not go away:

Minoxidil causes few side effects. Occasionally, the skin on the scalp may become red or irritated, causing itching. Body-wide side effects are possible if minoxidil is absorbed through cracks or cuts in the scalp. People with a history of heart disease, in particular, should watch for systemic side effects, such as
an increased heart rate, swelling in the hands or feet, or weight gain.