Welcome to HCM, Oh my, I do understand your concern. This is a very common side effect of some of the medications. The problem is..finding a medication that WORKS yet has low potential for gynomastia (enlargement of the breasts) or in some women, the excretion of milk. Yes, a good diet is a great recommendation as a starting point for addressing any problem. However, I do not know of any diet that will take care of this side-effect. Treatments for his condition range from banding, to trying another medication and monitoring closely coupled with behavioral therapy, to a brain scan to see if something is awry with his pituitary and I don t recommend the latter. Now, how important is diet in actually controlling OCD? Some physicians say that by eating foods that may increase serotonin in the brain will help, but I do not think anything beyond this should be done without seeing an integrative Dietitian or Physician. The foods he can try are: protein-rich foods like turkey, chicken, milk, eggs and cottage cheese; whole grains like brown rice and quinoa; beans and legumes; pumpkin; sunflower and sesame seeds; nuts; and root vegetables. I cannot emphasize the importance of psychotherapy. Ongoing cognitive therapy is very very beneficial. I hope I have given you an idea of something you can control to assist in your grandson s recovery. I will be blunt by saying there are many powders and pills that work on neurotransmitters. Individuals without such training to deal with these designer nutrients can do harm rather than good. You have a kind heart. I wish you and your family the best. Kathy J. Shattler,MS,RDN