January 28, 2013
Image of Methicillin 3D Image of Methicillin

Methicillin is a member of the penicillin family of antibiotics. Its synthesis from 6-aminopnicillanic acid was patented by F. P. Doyle and co-inventors in 1960. Methicillin is a narrow-spectrum drug that has been replaced by more stable and efficacious penicillin derivatives. Now it is best known as the M in MRSA (methicillin-resistant Staphylococcus aureus), a term for S. Aureus strains that resist all penicillins. In 2005, the International Pharmacopoeia guidelines changed the name of the drug to meticillin, but the original name is still widely used in the United States.

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