Ketoconazole which is the main ingredient of Nizoral, is a synthetic antifungal drug used to prevent and treat skin and fungal infections.
Believe it or not, this shampoo is usually prescribed for infections such as athlete's foot, ringworm, candidiasis, and jock itch. The over-the-counter shampoo version (which is about only 1%) can also be used as a body wash for the treatment of tinea versicolor.
The use of Nizoral definitely helps prevent hair loss. It has worked for me for sometime now. Use it daily for 14 days, twice (morning/night) and thereafter at least 1 or 2 times a week. Leave on for at least 3-5 mins. before rinsing and use a quality conditioner.
As an alternative on the 'off days' use Head and Shoulders. A recent study concluded that hair count results showed a modest and sustained improvement in hair growth with daily use of a 1% pyrithione zinc shampoo over a 26-week treatment period. Head and Shoulders main ingredient is pyrithione zinc.
Hope this info helps.