Broad-spectrum

The term broad-spectrum antibiotic refers to an antibiotic that acts against a wide range of disease-causing bacteria. A broad-spectrum antibiotic acts against both Gram-positive and Gram-negative bacteria, in contrast to a narrow-spectrum antibiotic, which is effective against specific families of bacteria. An example of a commonly used broad-spectrum antibiotic is ampicillin.

Broad-spectrum antibiotics are properly used in the following medical situations:

As a side-effect, antibiotics can change the body's normal microbial content by attacking indiscriminately both the pathological and naturally occurring, beneficial or harmless bacteria found in the intestines, lungs and bladder. The destruction of the body's normal bacterial flora provides an opportunity for drug-resistant microorganisms to grow vigorously and can lead to a secondary infection such as Clostridium difficile (also known as "C. diff") or Candidiasis (also known as "thrush"). This side-effect is more likely with the use of broad-spectrum antibiotics.

In humans:

In veterinary medicine, co-amoxiclav, (in small animals); penicillin & streptomycin and oxytetracycline (in farm animals); penicillin and potentiated sulfonamides (in horses).

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