I had a really bad reaction to Cymbalta.
I found www.drugs.com that has a medication interaction checker as part of the site. It is not a commercial site. Apparently Cymbalta and Amitryptaline can be very dangerous when taken together. My GP obviously didn't realise. The interaction checker is easy to use and you can check all your medications and if there could be an adverse interaction when taken together.
The site gives interactions for each medication combined so you can see ones that might be adverse. I kept on taking Cymbalta and Amitryptaline together and could not get out of bed, or even answer the phone for two weeks before I stopped taking Cymbalta. I honestly thought I was going to die but did not realise it was the side effects of the combination of medications.
If I had known about this site sooner, I had all the very dangerous side effects, I would have stopped Cymbalta combined with Amitryptaline straight away and gone back to my GP which is what they advise if you have adverse effects. It is not a commercial site and has lots of other information as well about medications. You do normally need the pharmaceutical name of the medication to check, although you can check with some brand names as well.