Hair Herbal Extract A non-prescriptive product containing herbal actives that are proven to neutralize DHT. DHT is the most common cause of hair loss. A leave-in treatment, the extract is massaged into the scalp twice daily. This product relies on a healthy, natural method of neutralizing DHT and encouraging blood flow to the scalp. Must be used with Nisim Shampoos Ð the extract is not a stand alone product. When you have achieved the desired results (typically 18-24 months), you can stop using the extract and maintain your hair using only the shampoo. This is not a product you have to use for the rest of your life. Also available as the Extract Gel.