This is an interesting question.
Getting a list of your prescriptions from the drug store is step one.
Then request the FDA handout for each of the drugs. This is not the one the drugstore prints up. Read the hand-out for every drug.
The list should then be presented to your physician.
There is pay database of drug interactions which is very good, but is is only available to physicians who pay the fee or medical schools. I am sure your physician will have access to such a database.
Without access to such a legitimate database, you cannot make an informed decision.
Make sure you are using only one pharmacy that way all your medications are on file there and they can check any interactions for you, especially when you get new Rx/medications.
Just my bit of advice.
I believe there is a site called drugs.com, this takes to a site that has a section for checking reactions to different drugs, etc.
I would say the best thing to do would get a print out at your local drug store and keep a list in your computer