if you are allergic (hypersensitive) to amoxicillin, clavulanic acid, penicillins or any of the other ingredients of Co-amoxiclav tablets (listed in section 6)
if you have ever had a severe allergic (hypersensitive) reaction to any other antibiotic. This can include a skin rash or swelling of the face or neck
if you have ever had liver problems or jaundice (yellowing of the skin) when taking an antibiotic.