Is there any down side to abruptly stopping taking Concerta? My 14.5 year old granddaughter quit taking the medication after 8 yrs. and now has headaches continuously and an enormous appetite. Could this be the cause of these recent symptoms and changes in appetite? Also, her grades have dropped drastically and she seems depressed at times. Don t know whether to consider this to be typical adolescent behavior or perhaps suddenly stopping this medication has contributed to these changes. She took 18 mg. in the morning with her breakfast before she stopped the medication.