Hi 2kids in Eureka, Which one of you wants to know? The only known side effects of Zerona laser are to your wallet. Thomas Barnes, MD of Newport Beach, CA spoke on behalf of Zerona last month in Beverly Hills and assured me that he has been using the same type of laser technology that Zerona uses (in a different hand held form) over the past 8 years without any complications or adverse effects what so ever. So far the only dangerous side effects that I have heard of are to the treating physician's reputation when dissatisfied patients complain. Patients need to continue exercising, eating properly, and living an appropiate life style for Zerona treatments to have a chance. I believe that when combined with exercise and diet, Zerona can be effective at reducing inches from the waist, hips, and thighs. There have been no reported internal or external complications from Zerona treatments that I know of. Good luck to both of you kids in Eureka, and be well. Dr. P