Action- Bacteriostatic (mainly) but when given at high dose then they act as Bactericidal,but keep in mind that in high dose risk of adverse effect also increases.
P/D- Stops protein synthesis of bacteria
Points to note-Food interferes with absorption of antibiotics so mostly antibiotics are taken on empty stomach.Previously the erythromycin was acid labile i.e it got destructed by the acid of stomach so it can’t act,but now new enteric coated erythromycin is made which survives even in acidic environment and can act easily against bacteria.
Macrolides increases intestinal motility and hence can treat constipation
Members of this group–
•Erythromycin– It has frequent dosing (given 4 times a day) , many bacteria have gain resistance against this drug.
•Roxithromycin– Less frequency of dosing ( given one to two times a day),less adverse effects as compared to erythromycin.
•Clarithromycin- It have some action against some special Bacterias also like- It can act against Helicobacter pylori, Mycobacterium leprae, Mycobacterium Tuberculosis, Mycobacterium avium intercellularae
•Azythromycin- It is a powerful drug with strong action against bacteria,it is given once daily for generally 3 days.Many Bacterias have still not gained resistance against this drug.It is also used against various gram negative bacillus bacteria (Enterobacteriaceae)
Adverse effects-
•Epigastric pain
•Loose motion
•Nausea
•Vomiting
•Hepatotoxicity
Uses-
Against gram positive bacteria like-
Staphylococcus aureus– causes skin infection
Streptococcus pneumoniae- causes pneumonia
Clostridium tetani- causes tetanus
Clostridium perfingens- causes gas gangrene
Against gram negative bacteria like-
Gonococcus– causes gonorrhoea
Bordetela pertusis– causes pertusis
Moraxella Catarrhalis– causes pneumonia
Haemophilus influnziae/ducreyi– causes pneumonia
Against atypical bacteria like-
Mycoplasma
Chlamydia
Against trepenoma palladium causes syphillis
Macrolides are also used in other conditions like of- Sinusitis,Rhinitis,
Rhino sinusitis, Pharyngitis, Laryngitis, Tracheo bronchitis, Otitis media
Contributor- Medico Anant Singh Nanda
