It could be one ot the combination of these, or it could be something else.

This is a great question for a Clinical Pharmacist or Nurse with a Pharmacy subspecialty. You provide a list of all prescriptions , over-the-counter-meds, supplements, "natural remedies", topical creams and lotions (like Ben Gay or similar) -everything that goes in or on your body, including the dosage & frequency of each, plus any allergies you have.
They have "interaction checker" tools and can see exactly where the issues might be. There are similar tools on-line, but theirs are more comprehensive.

Can you ask one of your doctors for a referral? Large clinical systems usually have these people on staff or on a consultant basis.

Sue