The objective of this study is evaluating and comparison of Cyproheptadine and Folic acid effects on appetite and hyperactivity and attention deficiency in children with ADHD receiving Ritalin. forty children referring to private psychology clinic at the age range of 7-12 who meet the inclusion criteria will divide in to two groups in a double blind permuted block randomized allocation design based on gender blocks. One group taking Cyproheptadine (12mg 4mg before each meal) combined with Ritalin (1mg/kg), and the other group taking Folic acid (5mg/day) combined with Ritalin (1mg/kg). In the first visit, personal and demographic questionnaires, special tests for ADHD (based on diagnostic criteria for DSM-IV) such as ADHD Rating Scale, appetite questionnaire, and SDSC (Sleep Disturbance Scale for Children) sleep questionnaire will complete by mothers; and then, anthropometric measurements in standard situation will perform. ADHD rating scale, appetite questionnaire and SDSC sleep questionnaires will be completed by mothers at baseline, and will repeat at 2, 4, and 8 weeks after the treatment. Anthropometric assessments will done at baseline and will repeat 8 weeks after the treatment. At the end of study, the stimulant drug side effects questionnaire will complete by mothers; then, the side effects will compare between the two groups.