@kathleenhalligan59 Tagrisso absolutely gave me diarrhea, too. I found that taking 1 imodium at the same time as the Tagrisso worked well for me without constipation. I eat a pretty high fiber diet, though. As far as dehydration, I add an electrolyte powder to my water all the time and it really helps me feel better. I like the one Ultima makes, but any of them would help.
https://www.amazon.com/dp/B01IIGQ5KG?