New Penicillin

Far from being a single, simple drug, penicillin is a whole family of drugs with slightly differing properties that determine which one is best for a particular illness. Together they make up the royal family of antibiotics. Last week the British were saluting the arrival of a new penicillin prince, Penbritin,* which promises to carry the fight against groups of microbes that have defied all previous penicillins. If it fulfills its early promise, Penbritin will become the first-choice drug against several forms of food poisoning, certain types of respiratory infections and meningitis, and possibly typhoid fever as well.

Early penicillins were active mainly against the berry-shaped microbes or cocci, such as streptococci, staphylococci and pneumococci. But they were ineffective against most rod-shaped bacteria. And most of them had two other draw backs: they were so quickly destroyed by digestive acids that they had to be injected directly into the bloodstream, and they were destroyed by the enzyme penicillinase. which is produced by resistant strains of staphylococci.

The breakthrough came in 1959 with the isolation of 6-aminopenicillanic acid, which is the hard core of all penicillin molecules. The new Penbritin is the first modification found to be active against a wider range of bacteria.

In the test tube, Penbritin has proved deadly to a variety of disease-causing microbes. Tried on a small number of British patients, it swiftly cleared up stubborn infections of the urinary tract, including some caused by the common colon bacteria, Escherichia coli. Test tube promise was not fulfilled in intestinal infections caused by one of the commonest forms of Salmonella; after a brief clearing, the microbes reappeared. More trials in many patients will be needed to show whether Penbritin can be useful against the several forms of Salmonella and Shigella that cause much dysentery and enteric fever, and, most importantly, against Salmonella typhosa, the microbe of typhoid fever. Two encouraging characteristics were noted by the British Medical Journal: Penbritin appears to be remarkably free of unwanted side effects, and it has the advantage that it actually kills the microbes, whereas drugs previously used only starved them out by preventing their multiplication.

* The chauvinistic trade name of Beecham Research Laboratories Ltd. for 6[D(--) a-amino-phenylacetamido] penicillanic acid. No simplified generic term or U.S. trade name has yet been adopted.

This file is automatically generated by a robot program, so reader's discretion is required.