Minoxidil is a vasodilator medication available over-the-counter (topical) or by prescription (oral) primarily used to treat pattern baldness and, in higher doses, severe hypertension. It stimulates hair growth, likely by increasing blood flow to hair follicles. Topical 2% or 5% solutions/foams are commonly used to treat hair thinning in men and women. 

Minoxidil is a medication that increases new hair growth in cases of hereditary hair loss. You can apply this topical solution or foam on your scalp to promote hair growth. The brand name of this medication is Rogaine®.

Key Details About Minoxidil:

• Hair Loss Treatment (Topical): Commonly known by brand names like Rogaine, it is used to slow hair loss and promote regrowth, particularly effective for people under 40 with recent hair loss.
• Mechanism: It works by increasing blood flow to the hair follicles and acting as a vasodilator, which relaxes blood vessels.
• Usage & Results: It is applied twice daily to a dry scalp. It requires consistent, long-term use; stopping treatment often leads to hair loss resuming within a few months.
• Side Effects (Topical): Common side effects include scalp irritation, dryness, itching, and unwanted hair growth in adjacent areas.
• Oral Use: Used for severe high blood pressure (hypertension) by relaxing blood vessels, often prescribed with other medications.
• Precautions: It is highly toxic to cats. It is not effective for receding hairlines. 

Side Effects & Warnings:

• Topical: Scalp irritation, unwanted hair growth (hypertrichosis).
• Oral: Fluid retention, weight gain, tachycardia (fast heart rate).