Antibiotic Therapy

Antibiotic therapy refers to the use of antibiotics to treat infections caused by bacteria. Antibiotics are medications that work by either killing or inhibiting the growth of microorganisms, such as bacteria, fungi, or protozoa.

Types of Antibiotics

  • Broad-spectrum antibiotics: Effective against a wide range of bacteria, including both Gram-positive and Gram-negative bacteria.
  • Narrow-spectrum antibiotics: Effective against a specific type of bacteria or a limited range of bacteria.
  • Penicillins: A class of beta-lactam antibiotics that include penicillin G, amoxicillin, and methicillin.
  • Cephalosporins: A class of beta-lactam antibiotics that include cefazolin, ceftriaxone, and cephalexin.
  • Fluoroquinolones: A class of broad-spectrum antibiotics that include ciprofloxacin, levofloxacin, and moxifloxacin.
  • Macrolides: A class of antibiotics that include erythromycin, azithromycin, and clarithromycin.
  • Tetracyclines: A class of broad-spectrum antibiotics that include tetracycline, doxycycline, and minocycline.

Indications for Antibiotic Therapy

Antibiotic therapy is indicated for the treatment of bacterial infections, such as:

Administration of Antibiotics

Antibiotics can be administered through various routes, including:

  • Oral: Tablets, capsules, or liquid suspensions taken by mouth.
  • Intravenous (IV): Administered directly into a vein using a needle and catheter.
  • Intramuscular (IM): Injected into a muscle using a needle and syringe.
  • Topical: Applied directly to the skin or mucous membranes using creams, ointments, or eye drops.

Dosage and Duration of Antibiotic Therapy

The dosage and duration of antibiotic therapy depend on various factors, including:

  • Type and severity of infection
  • Age and weight of the patient
  • Renal function (for patients with kidney disease)
  • Hepatic function (for patients with liver disease)
  • Pregnancy or breastfeeding status

Monitoring and Adverse Effects of Antibiotic Therapy

Patients receiving antibiotic therapy should be monitored for:

  • Adverse effects: Such as nausea, vomiting, diarrhea, allergic reactions, and Clostridioides difficile (C. diff) infection.
  • Renal function: To avoid nephrotoxicity (kidney damage).
  • Hepatic function: To avoid hepatotoxicity (liver damage).

Resistance to Antibiotics

The overuse and misuse of antibiotics have contributed to the development of antibiotic-resistant bacteria, making infections harder to treat. It is essential to use antibiotics judiciously and follow proper prescribing guidelines to minimize the risk of resistance.

Article last updated on: 18th June 2025.
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