What Are Sulfa Antibiotics?
Sulfa antibiotics are bacteriostatic drugs containing the sulfanilamide molecular structure. These drugs were the first chemical substances used for the treatment and prevention of various bacterial infections in humans, including respiratory infections, urinary tract infections, bronchitis, middle ear infections, intestinal infections, pneumonia, bacterial meningitis, and vaginal infections. Sulfa antibiotics are derived synthetically from sulfanilamide as well as other sulfa drugs.
The following medications belong to sulfa antibiotics:
• Trimethoprim (Proloprim, Trimpex, and Primsol);
• Co-Trimoxazole (Septrin);
• Sulfamethoxazole (Gantanol);
• Sulfadiazine;
• Trimethoprim-Sulfamethoxazole (Bactrim DS, Bactrim, Septra DS, and Septra);
• Sulfasalazine (Azulfidine, Azulfidine EN-tabs, and Sulfazine);
• Sulfisoxazole (Gantrisin).
Sulfa antibiotics do not destroy bacteria but inhibit their growth and multiplication thanks to interfering with their enzyme systems.
Historical Background
Prontosil was the first of many sulfa drugs and first medication used in the successful treatment of bacterial infections. Through the 1920s-1930s, Europe and the USA suffered from common bacterial infections, such as streptococcal, staphylococcal, tubercular, and pneumococcal infections. Sulfa drugs (sulfonamides) were introduced by Gerhard Domagk in 1935, which allows using them for the first successful treatment for lots of bacterial diseases. They were the forerunners of modern antibiotics, proving that bacterial infections can be fought with substances not natural for the body.
Side Effects
Sulfa antibiotics are effective in treating a range of infections, but they may also cause a range of side effects. These drugs are generally well tolerated and safe. The following are common side effects that you may experience if you use the antibiotics:
• Nausea;
• Tiredness;
• Sensitivity to light;
• Joint pain;
• Vomiting;
• Diarrhea;
• Headache;
• Pale skin;
• A minor rash;
• Itching;
• Loss of appetite.
Most of these side effects may be avoided if you do not use the drugs on an empty stomach.
Rarely, but this group of drugs may cause severe side effects, such as:
• Skin reactions, including TEN and SJS;
• Liver injury, including changing color of the skin and eyes.);
• Reactions related to changes in the blood;
• Kidney problems;
• Muscle damage;
• Neurological and psychiatric problems, such as hallucinations.
Warnings and Precautions
Taking sulfa antibiotics may affect the level of vitamin B9 and good bacteria in the body. People who have an allergic reaction to certain sulfa drugs, such as fosamprenavir and amprenavir may also have it to sulfa antibiotics.
The antibiotics should not be taken by pregnant women. They should also be avoided by breastfeeding mothers and infants who are less than 2 months old. Another condition that does not allow using sulfa antibiotics is severe anemia occurred due to folate deficiency.
Sulfa drugs especially antibiotics may cause severe allergenic reactions. According to data, adverse drug reactions occur in about 3% of patients taking sulfa antibiotics. This means that sulfonamides should be prescribed carefully. The following are typical signs of allergenic reaction:
• Facial swelling;
• Difficulty breathing;
• Feeling of the throat closing;
• Rash;
• Change in skin color;
• Bruising or bleeding.
In order to take these medications safely, tell your healthcare provider if you have any health condition, such as kidney, blood, or liver problems. Sulfonamides may cause blood disorders, especially if they are used for a long time.
It is important to make sure that sulfa antibiotics work well for you, and that is why you may require frequent observation by your healthcare provider. People who are older than 65 years may be more sensitive to the side effects of sulfa antibiotics.
You should notify your healthcare provider about using the antibiotics before having any kind of medical procedure, such as a dental exam.
The medicine may make your skin to be more sensitive to the sun, which means that you should avoid staying under the intensive sunlight for a long time. It is recommended to wear protective clothing and apply sunscreen.
Since sulfa medications may make you dizzy, you should avoid doing activities that require the clear state of mind, such as operating machinery or driving a car.
If you notice no improvement or even worsening your health condition, you should tell your healthcare provider.
Drug Interaction
Sulfa antibiotics may interact with lots of other medications, including the following:
• Warfarin (Coumadin);
• Diuretics;
• Antidepressants (Elavil).
In order to make sure that you will use sulfa antibiotics safely, you should consult your healthcare provider regarding all medications that you want to take along with this group of drugs, including the following:
• Prescription medications;
• Non-prescription medications;
• Illegal drugs;
• Recreational medicines;
• Herbal supplements;
• Nutritional supplements;
• Dietary drugs.