• U.S.

Medicine, May 6, 1946

2 minute read

Doctors who had been prescribing penicillin as casually as aspirin were suddenly socked in the midriff. The’reason: real knowledge about penicillin is pitifully small.

Unlike the finding of penicillin itself (TIME, May 15, 1944), the discovery of this fact was no accident. Three months ago two researchers discovered something that raised the eyebrows of penicillin experts, set them to rechecking furiously. Worried, they spot-checked hundreds of recently treated syphilis cases. The result was alarming: penicillin was apparently losing its wallop.

Last week, before the National Academy of Sciences, Johns Hopkins’ crack syphilologist, Dr. Joseph Earle Moore, trotted into the open a meager collection of recently discovered facts about penicillin (until now blanketed by wartime security): 1) instead of only one type of penicillin, there are at least four (arbitrarily named G, F, X, K); 2) type K is virtually useless because it is destroyed within the body so fast (in less than an hour) that it can’t get set for a knockout punch at the germs. In trying to produce a purer form of penicillin, drug companies had inadvertently made a product with high K content. (Commercial penicillin is a mixture of two to four types.)

Great Unknowns. Moore was not worried about relapses among patients treated with K-spiked penicillin. In all except syphilis cases, doses are so large that other types present quell bacteria; type K can be forgotten. If syphilis cases follow instructions (to report for regular checkups), any relapses will be nipped.

What did worry Moore was the paucity of information about the 20th Century’s most potent germ destroyer. Though the molecular structure of the mold extract had been virtually solved, chemists were still unable to synthesize it. The discovery of four types hinted that there might be more. Recent research indicated that the very impurities which manufacturers had striven to eliminate might be responsible for some of the drug’s efficacy. Why, no one knows. Could penicillin ultimately be broken into its component parts—each a remedy for a specific infection? Again, no one knows.

Said Moore: “The penicillin situation is just about where vitamin B research was 20 years ago.”*

*At that time vitamin B was thought to be a single factor. Further research ‘turned up at least ten factors, each good for a specific deficiency disease.

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