It can slow down the elimination of other drugs and result in you getting an overdose. That's probably why they told you to stop it, because that was easier for them than working out what the correct dose was with you taking curcumin.

When my husband needed his antispasmodic drug increased but we couldn't get it prescribed for two weeks, I gave him curcumin and he reduced his warfarin too (he measures his own INR so he can tell what he needs), that worked a treat!

My deceased husband finally ended up on gold salts, an old treatment, prescribed by Mayo Clinic. It was the only thing that worked after many years of trying, but this was a couple of decades ago. (He died of bladder cancer, not rheumatoid disease)