Teeth discolouration after quad therapy

Has anybody ever noticed brown stains on their teeth after treatment? I did the quad therapy with amoxicillin, clarithomycin, metro and pantoprazole.

About five weeks after stopping the antibiotics I saw the discolouration on my teeth. I was still taking the PPI and then I stopped when I saw the discoloration.

I only use an electric toothbrush, but no amount of brushing is helping right now.

Anyone with similar experience?