I recently had one of those months where I couldn’t figure out why I was itching at night. It drove me crazy. I cut back on edible histamines. I cut back on histamine liberators. I cut back on DAO inhibitors. I ate pea sprouts for the natural DAO. I checked my environment for any new triggers. I wondered if I’m getting old enough that hormonal changes are the problem and ate more cruciferous veggies to help clear any excess estrogen. Nothing made a difference. Then I remembered that my thyroid replacement medication had changed shape to a smaller pill a few weeks earlier and wondered if maybe my insurance had switched formulations or manufacturers. Perhaps a new excipient was the problem? Seemed like a promising lead, but how does one find and compare drug excipients?
DailyMed to the rescue! DailyMed is a database of drug information maintained by NIH.

DailyMed allows you to find your drug, your manufacturer, your dose, and then see the list of inactive ingredients. If you have MCAS or hypersensitivities, you might be surprised by how often the excipient lists include common allergens. For example, my thyroid replacement medications—which are extremely common—contain corn and dairy ingredients, food colorings, and more:


As you’ll see in the database, mosts drugs have multiple formulations (with different excipients) to try. If all formulations have excipients you don’t tolerate, you can ask to have your prescription made by a compounding pharmacy to suit your tolerances.
Sure enough, I learned that my new thyroid med had some new excipients I hadn’t tried before. Now it’s time to ask my doctor to prescribe the OLD version, to see if that fixes my problem.
This whole process is slow and frustrating, but at least DailyMed makes it a lot easier!