Hello. Pexep CR contains Paroxetine, a medicine used for treating depression and/or anxiety. The doctor who prescribes any medication for depression and/or anxiety has to interview the patient during each visit about the symptoms. Depending upon whether the symptoms have reduced or increased, the doctor may reduce or increase the doses too. Many a times, symptoms may be reduced, but not as quickly as is expected with the medication. In such cases, the doctor may increase to dose to speed up the process. This may be the case with your father. Your doctor may not have discussed it in detail, but he/she probably wasn't seeing significant improvement with a dose of 12.5 mg. Other than the primary reason why your father was started on Pexep, there's nothing to be worried about. During your next visit to the doctor, you can discuss with the doctor about the increased dose and his reason for the same, so that you will know for sure. But meanwhile, the abovementioned reasons seem to be the case. I hope this helps. Take care.