drug interactions

I started 2.5 mg daily this morning, AFTER I had a mango and grapefruit salad. Cruising the interwebs it appears that was the wrong fruit salad to enjoy with Cialis. Apparently grapefruit is a no no with many drugs, including Cialis. It looks like grapefruit inhibits breakdown of the drug so it...

I sent @Dr Justin Saya MD (my doc) a message, but not sure how soon he'll be able to respond. I am being put on a cancer med that interacts/has interaction warnings with CYP3A4 and CYP3A5. I have searched around the web and found precious few references for any contraindications or interactions...