Green Cream Level 9 is one of the most active skin care products on the market today without a prescription. We recommend that you start your retinol regimen with Green Cream Level 6. After 3 to 6 months use of Green Cream Level 6 on a daily basis, you should be able to slowly integrate Level 9 into your routine. Green Cream Level 9 makes an excellent alternative to a prescription strength retinoid. It is recommended that you begin using Green Cream Level 9 every other night and gradually advance to daily use as the skin acclimates.