Sulfonamides 1935 – Antibacterial Drugs

Ekkehard Grundmann: 

“With Gerhard Domagk began an era of tremendous victories against infectious diseases. Before sulfonamides, 30% of patients with meningitis died; the same statistic applied to pneumonia and tonsillitis, inflammation of one or both tonsils. In addition, one in every seven women died of postpartum sepsis, a serious infection. This changed from 1935 onwards.”

Sulfonamides – sometimes called sulfa drugs –  are a class of chemical compounds, some with antibacterial properties. In 1932, German bacteriologist Domagk, while testing a dye-based sulfa drug called Prontosil, identified a drug active against Streptococcus bacteria. Prontosil became the first medicine that could be used systemically to treat a range of bacterial infections in humans. It had barely been tested when Domagk hurriedly began experiments to save his daughter from an operation: an infection in her arm had put her at risk of amputation. 

In 1935, he published the successful results of his clinical experiment, in which his daughter's arm healed completely. Interestingly, Prontosil did not show antibacterial properties in test tubes.

In 1936, Swiss pharmacologist Daniel Bovet discovered that chemical reactions in the body split the sulfonamide into an inactive dye component and a colourless active compound, sulfanilamide.

In the early 1940s, researchers discovered that sulfanilamide suppressed bacterial folic acid synthesis, preventing bacteria from multiplying and improving the body's immune system's chances of fighting infection. 

The only effective antibiotics available before penicillin treatment, sulfa drugs saved countless lives during and after World War II. 

Although other antibiotics are usually preferred today, sulfa drugs may still be used when bacteria develop antibiotic resistance.

In 1939, Domagk was awarded the Nobel Prize in Medicine for discovering the sulfonamide Prontosil. However, Nazi authorities did not allow him to accept the award because of his criticism of the Nazi regime.

Description of the article image: Before sulfonamides were used, 30% of patients with meningitis died. The meningococcus bacteria shown in this colourised image can infect the membranes of the central nervous system.

Historical figures mentioned in the article: Gerhard Johannes Paul Domagk (1895–1964), Daniel Bovet (1907–1992)

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