About erythromycinmacrolide antibiotic.mechanism of action of erythromycinerythromycin is a member of macrolide antibiotics. it binds to the 50s sub unit of bacterial ribosome and inhibits translocation.ie: they interfere with the transfer of the newly formed peptide chain from the a site to the p site and fails to expose the a site .so that a site is unable to bind with the next aminoacyl t rna complex. this leads to premature termination of amino acid chain and there by inhibits protein synthesis.interactions for erythromycinanticoagulants: efficacy enhanced leading to haemorrhages. bromocriptine: efficacy protentiated leading to toxicity. carbamazepine: dangerous toxic side effects requiring resuscitative measures and hospitalisation. digoxin: serum levels of digoxin enhanced, leading to toxicity. disopyramide: increased disopyramide plasma levels leading to arrhythmias. ergot alkaloids: acute ergotism manifested as peripheral ischaemia.