When it comes to medication, it’s very important to maintain a regular schedule in order to avoid further health risks. Perhaps making an appointment with his doctor or reaching out to other healthcare professionals can help him see the necessity of staying active with his medicines. It’s important not to force anything, but try to facilitate a two-sided conversation so you can hear your father's concern. Remember that as people get older, they may resist doing things because they are at a point in their lives where they are becoming more dependent and feel like they are losing control of their lives.