Sorry to hear of your issues. Drugs and related drugs that can cause Anaphylaxis (such as Penicillin in some), must be carefully watched. I was on a Beta-Blocker known to interact with a medication a neurologist was trying to prescribe. I told him so, and he said I was wrong. I refused to accept it from him, so he phoned a cardiologist friend of his. After getting off the phone, it was now "Let's take you off your medication first, and then we'll start this". And to think many people walk out with prescription in hand. Pharmacists are people to talk to about interactions, possibly more knowledgeable than the Doctor. Years later, also on a Anti-Epileptic Drug, I had to inform another physician that the antibiotic he was prescribing was contraindicated by my medication. He corrected it with no protest. The pharmacy likely would have caught it as well.

I can't advise medically, I hope you find the source. Though not advocating the medication, after suffering pain in my arm (not heart related) for months, I went to the doctor, he prescribed Orudis (Spelling? And I don't think it's on the market anymore). It's chemically related to Ibuprofen, and I figured it wouldn't work, as I tried Ibuprofen already. Voila, the pain went away. Sometimes it takes a while to figure out the correct medication for the particular problem. Keep in touch with the Doctor.