<p>May enhance the action of neuromuscular blocking agents (e.g. atracurium). May antagonise the effects of parasympathomimetics. May competitively inhibit the effects of macrolides, ketolides, streptogramins, linezolid and chloramphenicol. Increased coagulation tests (prothrombin time/INR) and/or bleeding with vit K antagonists (e.g. warfarin, acenocoumarol, fluindione). PABA sunscreens may transiently discolour fabric.</p>