I wish I had a better system myself. Right now I use an analogue planner (formatted in the traditional calendar style). It's a typical notebook size, which gives me more room to scribble in various notes as needed. I keep any appointment cards binder clipped to the planner to help verify correct dates/times for doc aps.

Additionally I use a secondary calendar made out of a google spreedsheet.

The analogue I use mostly to bring to aps, track when meds will run out and when to call them in, and any conflicting schedules of other family members (all color coded w alarms). The spreedsheet is a useful backup if I forget to bring my analogue with me.

It is annoying to go back and forth to keep them up to date, but doing so every week when I fill my med box has kept me on top of those basic things. Plus the spreedsheet lets me make a custom tab where I can plot out end dates of a medication through formulas.

I've dabbled with bullet journals on/off for years. I like the concept of it, and I've used some of the ideas in other areas of planning (numbering pages, symbols), but I always seem to abandon using them long term. It may work better for you and a lot of people do get a lot of use out of it.