Requesting the unfeasible

I have completed seven weeks of treatment with Sertraline and, after a challenging start, I am now feeling back to my usual self. Recently, I started using Lanzoprazole again to address my acid reflux, which had been prescribed previously but hadn't been used in over a year.

Within a day of starting the Lanzoprazole, I experienced diarrhea, initially assuming it was due to something we ate or a virus since my husband also had mild symptoms. However, his issues resolved after a couple of days, whereas mine have persisted despite stopping the medication two days ago. The diarrhea is improving but continues nearly a week later.

I am unsure if the cause is the Sertraline (which didn't previously lead to this symptom), the Lanzoprazole, or possibly IBS, which I was diagnosed with several years ago. Additioanlly, I take Levothyroxine and have B12 injections every eight weeks, and one of my kdineys was removed eleven years ago because of a 15.8 cm cancerous growth. A scan at the time also showed a large stone in my gallbladder, but no action was taken as it hasn't caused problems since.

With all these factors, I am unsure what might be causing the diarrhea. If anyone has any suggestions, I would appreciate them. Specifically, could it be due to the Sertraline? Could it be from the Lanzoprazole? Or is it a combination of both?