I am on warfarin because of my AF and my GP has prescribed 3 separate courses of Amoxicillin to try and get ride of my chest infection that I have had for about 8 weeks. I still have a wheezey chest at night and my GP is reluctant to prescribe other antibiotics as he is concerned that it will affect my INR adversely. My INR is normaly rock steady at 2.5. Any advice about other antibiotics? Should I change to a NOAC - do they have the same problem? All advice welcome.