Sulfonamides (Sulfa Drugs) in Survival

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The availability of antibiotics to the family medic in survival and other austere settings may prevent the unnecessary deaths of loved ones due to infection. When help is not on the way, the average citizen will find these drugs to be important tools in the medical woodshed.

You might think that Penicillin family drugs were the first to be used by the general public, but another popular family of antibiotics called sulfonamides, or sulfa drugs, were actually on the market even earlier. Indeed, it has been called “the first miracle drug”. Sulfonamides deserve credit for saving tens of thousands of lives during World War Two. It was so widely used that many soldiers’ first aid kits came with the drug in pill or powder form. Medics were told to pour it into any open wound.

Sulfonamides were first identified to have antibacterial action by a German scientist named Gerhard Domagk, who evaluated certain dyes for possible medical uses. He found a red dye produced by Bayer (yes, that Bayer) that apparently eliminated bacterial infections in mice. This became “Prontosil”, credited as the first broad-spectrum antibiotic. Interestingly, it didn’t show a lot of antibacterial action in test tubes; Prontosil’s effect was much more noticeable on a live subject.

Another interesting tidbit about Sulfa drugs is that the active ingredient had been used by the dye industry for decades, so no patent could be obtained. Bayer had to share the ingredient with anyone who wanted to use it, eliminating the potential for big profits. This led to many different variations, some of which were “snake oil” that contained toxic ingredients. One such elixir killed a hundred people in 1937, leading to the enactment of the first serious oversight of pharmaceuticals, the Federal Food, Drug, and Cosmetic Act of 1938.


Sulfonamides act to inhibit an enzyme involved in folate synthesis, an important aspect of bacterial DNA production. This family of drugs is bacteriostatic; that is, they don’t directly kill the bacteria, but inhibit growth and multiplication. If bacteria are unable to multiply, they can’t sustain the population needed to damage the body.

A commonly used sulfonamide is the combination drug sulfamethoxazole 400 or 800mg and trimethoprim 80 or 160 mg, known by the brand names Bactrim or Septra in the U.S. In Great Britain, it is called Co-Trimoxazole (Cotrim). A veterinary equivalent is known as Fish-Sulfa or Bird-Sulfa.

ASIDE: Different antibiotics (or other drugs) may be combined into one product. Usually, this is done because the two work together to have a stronger effect against an infection or other condition than they would if used alone. This is called “synergism”.


Broad-spectrum Sulfamethoxazole/Trimethoprim is effective in the treatment of many infections, including:

· Some upper and lower respiratory infections (chronic bronchitis and pneumonia)
· Kidney and bladder infections
· Ear infections in children
· Cholera
· Intestinal infections caused by E. coli and Shigella bacteria (a cause of dysentery)
· Skin and wound infections, including MRSA
· Traveler’s diarrhea
· Acne

Of course, as an antibiotic, no sulfonamide has any effect on viruses or viral illnesses.


The usual dosage in adults is sulfamethoxazole 800-mg/Trimethoprim 160mg twice a day for most of the above conditions for 10 days (5 days for traveler’s diarrhea).

The recommended dose for pediatric patients with urinary tract infections or acute otitis media (ear infection) is 40 mg/ kg sulfamethoxazole and 8mg/kg trimethoprim per 24 hours, given in two divided doses every 12 hours, for 10 days. 1 kilogram equals 2.2 pounds. This medication should not be used in infants 2 months old or younger.

In rat studies, the use of this drug was seen to cause birth defects; therefore, it is not used during pregnancy.
Another sulfa drug, Sulfadiazine, is combined with Silver to make Silvadene, a cream useful for aiding the healing process in skin wounds and burns. Cover completely twice a day.

Sulfamethoxazole/Trimethoprim and other Sulfonamides are well known to cause allergic reactions in some individuals. These reactions to sulfa drugs are almost as common as Penicillin allergies, and usually manifest as rashes, hives, and/or nausea and vomiting. Worse reactions, however, can cause blood disorders as well as severe skin, liver, and pancreatic damage. Those with conditions relating to these organs should avoid the drug.

Although an allergy to Sulfa drugs may be common, it is not the same allergy as to Penicillin. Those allergic to Penicillin can take Sulfa drugs, although it’s possible to be allergic to both.

Sulfonamides and other antibiotics aren’t candy, and they must be used wisely and only when absolutely necessary. In normal times, seek out qualified medical professionals before you consider their use.

Joe Alton MD

Learn more about Sulfa Drugs and other survival antibiotics in the Book Excellence Award winner in Medicine, The Survival Medicine Handbook: The Essential Guide for when Medical Help is Not on the Way, available on Amazon or this website.

Hey, don’t forget to check out our entire line of quality medical kits and individual supplies at Also, our Book Excellence Award-winning 700-page SURVIVAL MEDICINE HANDBOOK: THE ESSENTIAL GUIDE FOR WHEN HELP IS NOT ON THE WAY is now available in black and white on Amazon and in color and color spiral-bound versions at

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