Overview and qualities of antibiotics

Antibiotics are vital treatments for bacterial infections and are essential in modern medicine.
Awareness of how antibiotics function is crucial for responsible use.

Many patients misuse antibiotics by taking leftover medications for inappropriate conditions like headaches.
Antibiotics should be reserved for confirmed bacterial infections only, not for mild infections or viral infections.
Key point: Antibiotics are chemical agents designed to kill bacterial cells.
- Anything that can kill a bacterial cell is toxic. Meaning if someone took to high of a dose of an antibiotic not only would it be dangerous to the bacteria but it’ll be dangerous to human cell as well.

Taking antibiotics at high doses can be harmful to both bacteria and human cells, emphasizing the need for careful management.
Importance of using antibiotics judiciously in society.

Antibiotics selectively target bacteria; they are ineffective against fungal and viral infections:
- Fungal infections require antifungal medications.
- Viral infections require antiviral medications.
No single antibiotic can kill every pathogen; the goal is to find alternatives that effectively kill bacteria while minimizing harm to human cells.

Alexander Fleming discovered antibiotics in 1928 while researching bacteria.
- Grew staph aureus bacteria in a petri dish and observed a fungus creating a zone of clearing around it.
- The fungus was found to secrete a toxin that killed the surrounding bacteria.
- This toxin is now known as penicillin, a natural antimicrobial.

Natural Antimicrobials: Produced by fungi or bacteria to eliminate competitors, e.g., penicillin.
Penicillin is very effective for gram + bacteria but not so effective for gram - bacteria.
Semi-synthetic Antibiotics: Derived from natural antimicrobials but altered to enhance efficacy, e.g., ampicillin from penicillin.
- Ampicillin comes from penicillin and penicillin was tweaked because it is only effective for gram + so ampicillin is very effective for both gram + and gram -.
- Amoxicillin is another semi-synthetic antibiotic that is very effective for gram + and gram - bacteria.
Synthetic Antibiotics: Created entirely in the lab to combat bacterial infections.

Selective Toxicity: Target bacterial cells without harming human cells.
- Selectively toxic to the microbe but nontoxic to host cells.
Microbial Cidal: Preferably kill bacteria, characterized by the suffix "-cidal".
- Microbicidal rather than microbistatic. -cidal means to kill. So Microbcidal means to kill bacteria. -static means to inhibit. So microbistatic means to inhibit or slow the growth but doesn’t kill it.
Microbial Static: Inhibit bacterial growth rather than kill them, characterized by the suffix "-static".
Potency Duration: Remain active in the body long enough to be effective it’s not broken down or excreted prematurely.
Resistance Prevention: Minimize the chances of bacteria developing rapid resistance.
- Note: All drugs will eventually face resistance due to evolutionary pressures on bacteria. and will become ineffective.
Cost-effective: Reasonably priced for accessibility.
Targeted Delivery: Administered based on the infection type, whether orally or intravenously.
Low Side Effects: Few allergies or adverse reactions among patients.

Spectrum: range of activity of the drug.
Narrow Spectrum: Targets specific bacteria types, e.g. penicillin targets primarily gram-positive bacteria.
Medium to Broad Spectrum: Affects a wider range of bacteria.
- Examples:
- Ampicillin: Medium spectrum, effective against some gram-negative bacteria.
- Tetracycline: Broad spectrum, effective for both gram-positive and gram-negative bacteria.

Narrow spectrum drugs preferred to avoid disrupting normal flora.
- Broad spectrum antibiotics risk leading to superinfections by eliminating beneficial bacteria.

Defined as secondary infections occurring as a result of disrupting normal flora by broad-spectrum antibiotics.
- The antibiotic kills the normal flora or inhibits them or changes them in some way and a secondary infection occurs.
  - Examples include:
  - C. Diff Infection: After normal gut bacteria are killed, C. difficile proliferates, leading to severe diarrhea and toxicity.
  - Yeast Infections: Occurs when antibiotics kill beneficial vaginal or oral flora, allowing yeast to overgrow.

Allergies to antibiotics, particularly penicillin, are common and can arise from prolonged use.
Some antibiotics, such as tetracycline, can cause significant side effects, like tooth discoloration in children and pregnant women.
Antibiotics can also pose risks of toxicity affecting organs like the kidneys and liver.

Healthcare providers must weigh the benefits of prescribing an antibiotic against the potential risks and side effects for the patient.
Factors include the severity of the infection, possible adverse reactions, and the likelihood of contributing to antibiotic resistance.