Penicillins, development

Methicillin is a semisynthetic penicillin that also resists the action of -lactamases and, thus, is frequently used for penicillin G-resistant staphylococci. It is the first semisynthetic penicillin developed but it is poorly absorbed when given orally due to its instability in gastric acid. Absorption is better when it is administered intravenously or intramuscularly. Methicillin is principally eliminated in the urine but small amounts are also found in bile and other body fluids. 

Note Penicillin and cephalosporins share a common beta-lactam structure. People who are allergic to penicillin are approximately 4 times more likely to develop an allergic reaction to a cephalosporin than those people who have no penicillin allergy. (From 5 to 16% of patients allergic to penicillin develop reactions to cephalosporins)... 

Injection-site pain (5.7%) patients allergic to penicillin develop allergic reactions to... 

The agricultural industry contributed, through its fermentation facilities and com steep liquor used for the medium of culture, to penicillin development. The production of penicillin increased by more than 10-fold. In fact, by 1944, there was sufficient penicillin to treat all of the severe battle wounds incurred on D-day at Normandy. Also, diseases like syphilis and gonorrhea could suddenly be treated more easily than with earlier treatments. 

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