Hello and Welcome to Ask A Doctor service. I have reviewed your query and here is my advice. The medicine in Cypon is an antihistamine and some antihistamines are appetite stimulants. Cypon contains this kind of antihistamine. You are correct that Cypon is more often for allergic conditions ; the Cypon antihistamine also treats people s allergies. Side effects of appetite stimulants are nausea, vomiting, abdominal pain, blurred vision, fatigue, nervousness and dizziness and they should be avoided if the patient has diabetes. Unfortunately you have shared very little about your daughter s problem. But as I wish to help you and her, allow me to take you in a direction that just might assist you. Anorexia nervosa is a common eating disorder that affects adolescent females. Characteristics are the patient sees herself as being too fat even when she is underweight, refuses to keep a normal body weight, intense fear of becoming fat, excessive exercise, absence of three or more menstrual cycles without another cause and denies feeling hungry. She may be socially withdrawn, irritable, depressed, have abdominal pain, and fatigue. This condition is most serious. IF this is what she has, it can progress to need for hospitalization and even passing away. She needs to have a medical evaluation in more than a superficial way. This to include a complete general physical examination because the reason for poor appetite could be something else. Should the pediatrician who does the complete physical agree that an eating disorder is possible, than your daughter needs to be evaluated by a child and adolescent psychiatrist who is experienced in treating adolescents with eating disorders. Please think about what I have typed. Certainly discuss with your husband. And select a physician(hopefully a pediatrician that both of you trust) who will agree to speak with you(even if he/she requires payment) alone about her situation. Hope I have answered your query. Let me know if I can assist you further. Arnold Zedd, MD, FAAP