Broad-spectrum Antibiotics: Functions And Resistances

Broad-spectrum antibiotics are those that are effective in killing large numbers of bacteria. Find out what they are, how they work and what are the consequences of their abuse.

Broad spectrum antibiotics

Broad spectrum antibiotics are those capable of greatly reducing the bacterial load,  destroying a large number of microorganisms of different types. On the other hand, narrow-spectrum antibiotics are specific to a specific bacterial type.

They are normally bacteriostatic.  That is, they do not completely destroy bacteria. Instead, they prevent their growth and reproduction. As a consequence, the bacterial population ends up disappearing. The mechanism of action consists of inhibiting the synthesis of proteins in the bacteria that prevents their growth.

Due to their effectiveness, one of the big problems is that they can eliminate, in addition to pathogenic bacteria, others that are beneficial for our endogenous flora.

There are a large number of antibiotics. This is due to the development of new antibiotics to replace the previous ones, already ineffective, as a consequence of the resistance problem to these drugs.

Amoxicillin and clavulanic acid (AMC)

This type of antibiotic has a different mechanism of action. It is an association between two compounds.  On the one hand, amoxicillin prevents the synthesis of the bacterial wall, while clavulanic acid preserves the function of amoxicillin, enhancing it.

It is the most widely used broad-spectrum antibiotic in Spain. It is commonly used to treat respiratory infections. Due to this widespread and lax use, AMC is generating a large amount of resistance  and causing a global health problem.

Tetracyclines

Tetracyclines encompass a series of compounds with a common chemical structure and mechanism of action. All of them are focused on inhibiting protein synthesis in bacteria.

Its use in medicine is quite limited. This is due to its possible toxic effects on the body. They are usually administered to combat chlamydia, brucellosis or Mycoplasma .

Chloramphenicol

Chloramphenicol also works by inhibiting bacterial protein synthesis. It is used to treat Salmonella infections , and some meningitis and pneumonia. This antibiotic interferes with the enzymatic functioning of the liver, so its administration is carefully evaluated.

Macrolides

These types of antibiotics are also considered broad spectrum, although it is more limited. The prototype for macrolide antibiotics is erythromycin. Like the previous ones, its mechanism of action is to inhibit protein synthesis.

Erythromycin is considered one of the least toxic antibiotics. It is used to treat certain pneumonia, caused by  Mycoplasma pneumonia or Legionella pneumophila.

Resistors

Broad-spectrum antibiotics can be a great option for the treatment of certain infections, but  their excessive use generates a great health problem  due to resistance.

Any antibiotic is capable of generating resistance.  The bacterial strains that are attacked can mutate and evolve rapidly, with some eventually becoming resistant to the compound.

The problem extends when these resistant strains continue to infect the population  and there is no effective antibiotic against them. Because of this, new antibiotics (second and third generation) have been developed. However, the problem continues and new resistance continues to emerge.

The misuse of broad-spectrum antibiotics becomes especially problematic. By affecting a large number of microorganisms, it can generate multi-resistance in all of them.

Also, there is the problem of cross resistance. This happens when, due to a broad-spectrum antibiotic, a bacterial type also becomes resistant to other narrow-spectrum ones.

For all this, it is essential to make the population aware of the danger of the misuse of antibiotics.  Resistance is already affecting global health and leads to the appearance of infections that, until now, were considered controlled.