At a time when we have become so concerned about the overuse of antibiotics, doctors have become just as vigilant in only prescribed when needed. If they do so, they would make their selection based on five basic criteria: effectiveness, appropriateness, cost, ease of use, and avoidance of side effects.
To determine the antibiotic appropriate to your infection, your doctor would consider the following:
The Type of Bacteria Involved
Bacteria are divided into two types depending on their external structure:
- Gram-positive bacteria which has thick, waxy external layer
- Gram-negative bacteria which has an extra fatty layer that acts as a barrier against certain antibiotics
When choosing an antibiotic, your doctor would first consider the type of bacteria involved. This will determine, in part, which drugs can are most capable of penetrating the external barrier or damaging the structure enough to prevent it from replicating.
The Action of the Antibiotic
The different classes of antibiotics are divided according to the part of the bacterium they affect. For example, all penicillin-class antibiotics (ampicillin, amoxicillin) block the formation of the external waxy layer of the bacteria. Other classes attack the replication cycle of the bacteria, including cell division and protein synthesis needed to reproduce.
Antibiotics are further divided into bactericidal antibiotics (which kill bacteria) and bacteriostatic antibiotics (which stop them from growing). For some infections, limiting bacterial growth is sufficient enough to allow the body’s natural defenses to fully eradicate the bacteria.
How the Antibiotic Is Administered
Depending on the type and location of the infection, the choice the antibiotic will differ. Eye infections can often be treated with antibiotic eye drops while cuts and scrapes can be relieved with topical ointments. Other infections, such as urinary tract infections or pneumonia, may require pills.
As a general rule, oral antibiotics are stronger than topical antibiotics. Intravenous antibiotics, by contrast, are stronger than both. But strength should only play a part in the selection of the right formulation. It is ultimately about the appropriateness of strength that matters more than just “hitting the infection hard.”
The Course of Antibiotic Therapy
When it comes to antibiotics, the lesser the pill count the better. The simple fact is that people will usually stop taking an antibiotic as soon as they feel better. And that’s a mistake. Not only does it increase the likelihood of recurrence, but it also promotes the development of drug resistance.
Antibiotics work by eliminating the majority of bacteria while allowing the immune system to take care of the rest. By not completing a course of antibiotics, the surviving bacteria have the opportunity to thrive, some of which may be fully or partially resistant to the antibiotic. If these are allowed to predominate, antibiotic-resistant strains and superbugs can develop.