Uses
Gramicidin is active against Gram-positive bacteria, except for the Gram-positive bacilli, and against selective Gram-negative organisms, such as Neisseria bacteria. Its therapeutic use is limited to topical application, as it induces hemolysis in lower concentrations than bacteria cell death so cannot be administered internally. Since the exterior epidermis is composed of dead cells, applying it to the surface of the skin will not cause harm.
It is used primarily as a topical antibiotic and is one of the three constituents of consumer antibiotic polysporin ophthalmic solution.
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