Well, I am deficient on the record keeping. Taking over 30 tablets / capsules every day (mostly supplements), it is difficult to attribute causation when adverse effects and unwanted interactions come up, unless it happens right at the start. I have to stop most of them and then add back one at a time, which takes weeks, but this often still doesn’t catch the culprit. Also, things tend to be inconsistent and a supplement that causes GI problems at one point might be entirely benign the rest of the time.
One thing that has proven helpful though is the Chatbots. When given a long list of supplements and RX drugs the LLMs can very thoroughly go through and discover possible interactions and individual troublemakers.
I treat pill taking as a scientific experiment. Only one variable can be tested at a time. If the doctor wants 2 changes, we hold one off until the first change has been thoroughly evaluated. Only then can the next change take place.