According to Dr. Clark it's 3 capsules 3 times a day. I believe for 2 weeks, but look under Dr Clark's page to make sure. (listed under parasite cleanse) When I started the l-cysteine I took one capsule once a day. Now I'm up to 2 caps. once a day. I have a very sensative stomache so I've gone up very, very slowly. But that's just my needs, my husband did the full dose right away!