Alterna® enzymetherapy® Anti-Aging. Seasilk® Alterna shampoos improve the way your hair performs. Stress from the environment, the sun, aging, chemical services and everyday styling damages hair and leaves it brittle, dull and lifeless. This sulfate free cleanser infused with Seasilk®, Age-Control Complex™ and Photozyme Complex™ with Color Hold™ restores volume, protects color and improves the overall performance of fine, brittle hair. Enzymetherapy® - The Science of Skincare for Hair™ Made in USA.