Antibiotics Overview Quiz

Antibiotics, Antivirals, Antifungals

• Penicillins (broad spectrum):

  • Action: Beta-lactam ring interferes with bacterial cell wall synthesis.
  • Indication: Otitis media, tonsillitis, sinusitis, respiratory and urinary tract infections (gram-positive and gram-negative bacteria), endocarditis.
  • Adverse effects: GI: nausea, vomiting, diarrhea, abdominal pain, skin discoloration, superinfection, anaphylaxis.
  • Misc.: Allergy, hypersensitivity to cephalosporins, pseudomembranous colitis, ulcerative colitis, GI disease, decreased effect with acidic foods and drinks. May decrease effectiveness of oral contraceptives. Not effective against gram-negative bacteria.

• Penicillinase-Resistant Penicillins (e.g., Nafcillin):

  • Action: Treat penicillinase-producing S. aureus.
  • Indication: Endocarditis, meningitis, skin, respiratory, bone/joint infections.
  • Adverse effects: GI: abdominal pain, nausea, vomiting, diarrhea, renal impairment, skin stomatitis.
  • Misc.: Not effective against gram-negative bacteria.

• Cephalosporins:

  • Action: Inhibits bacterial cell wall.
  • Indication: Otitis media, meningitis.
  • Adverse effects: GI distress, phlebitis, injection site reaction, elevated.
  • Misc.: Caution: hypersensitivity to penicillins.

• Ceftriaxone (3rd generation):

  • Action: antibacterial synthesis causing cell lysis.
  • Indication: Gonorrhea, bacteremia, respiratory, bone/joint, abdominal, and urinary tract infections (gram-positive and gram-negative bacteria).
  • Adverse effects: Hepatic enzymes, pseudomembranous colitis, nephrotoxicity.
  • Misc.: Increased bleeding if used with anticoagulants.

• Cefepime (4th generation):

  • Action: inhibits bacterial cell wall.
  • Indication: Bacteremia, respiratory, skin, intraabdominal, and urinary tract infections.
  • Adverse effects: GI distress, headache.
  • Misc.: Caution: hypersensitivity to penicillins.

• Macrolides (broad spectrum):

  • Action: Bind to 50S ribosomal subunits to inhibit protein synthesis.
  • Indication: Respiratory infections
  • Adverse effects: GI distress, diarrhea.
  • Misc.: Interactions: theophylline, carbamazepine, and warfarin
  • Erythromycin, Azithromycin:
    • Action: Bacteriostatic (at low concentrations).
    • Indication: respiratory infections, pneumonia, GI distress
    • Adverse effects: diarrhea, abdominal cramping.
    • Misc: "Zpack"- use over 7 days with slow taper.

• Lincosamides (e.g., Clindamycin):

  • Action: Inhibits bacterial protein synthesis.
  • Indication: Lower respiratory tract infections, STIs and skin infections.
  • Adverse effects: GI distress, bone marrow suppression, pseudomembranous colitis.
  • Misc.: Not effective against gram-negative bacteria.

• Glycopeptides (e.g., Vancomycin):

  • Action: Inhibits bacterial cell wall synthesis.
  • Indication: Active prophylaxis against severe gram-positive bacteria, bacteremia and C. diff infections
  • Adverse effects: Nephrotoxicity, ototoxicity, red man syndrome, cardiac issues, permanent hearing loss, headache, dizziness, fatigue
  • Misc.: Monitor levels, peak and trough, dilute IV.

• Tetracyclines (e.g., Doxycycline):

  • Action: Inhibits bacterial synthesis.
  • Indication: Respiratory, urinary tract and skin infections, STDs.
  • Adverse effects: GI distress, hepatotoxicity, bone damage, teeth staining, rash, photosensitivity
  • Misc.: Contraindicated in children under 8, first and last trimester of pregnancy.

• Aminoglycosides (e.g., Gentamycin):

  • Action: Inhibits protein synthesis, bactericidal.

  • Indication: Serious infections.

  • Adverse effects: Nephrotoxicity, ototoxicity, CNS confusion, disorientation.

  • Misc.: Check peak and trough levels, increased risk of ototoxicity with diuretics.

• Fluoroquinolones (e.g., Ciprofloxacin, Levofloxacin):

  • Action: Interferes with DNA enzymes, necessary for bacterial synthesis.

  • Indication: Urinary tract, bone and joint infections, bronchitis, pneumonia

  • Adverse effects: Elevated CNS effects including headache, dizziness and insomnia, rash GI distress

  • Misc.: Reserved for patients with no alternative treatment options. Take before meals without antiacids.

• Sulfonamides (e.g., Trimethoprim-Sulfamethoxazole):

  • Action: Inhibits synthesis of folic acid, essential for bacterial growth.

  • Indication: Urinary tract, respiratory, ear infections.

  • Adverse effects: GI distress, CNS effects (headache, dizziness, vertigo, ataxia, depression, seizures), hepatotoxicity, nephrotoxicity, bone marrow suppression.

  • Misc.: Combination drug.

• Nitroimidazoles (e.g., Metronidazole):

  • Action: Disrupts DNA and protein synthesis.

  • Indication: Intraabdominal and respiratory infections, H. pylori

  • Adverse effects: CNS effects, GI effects, hepatotoxicity, nephrotoxicity, photosensitivity, rash.

  • Misc.: Given PO, IV, or topically. Avoid ETOH

• Antituberculars (e.g., Isoniazid):

  • Action: Inhibits bacterial cell wall synthesis.

  • Indication: Treat active tuberculosis and prophylaxis.

  • Adverse effects: GI distress, peripheral neuropathy, hepatotoxicity, ocular toxicity.

  • Misc.: Contraindicated: moderate to severe liver disease, Monitor LFTS.

• Antimycobacterials (e.g., Rifampin):

• Action: Inhibits bacterial cell wall synthesis.

• Indication: Tuberculosis.

• Adverse effects: Body fluids may turn orange, hepatotoxicity.

• Misc.: Given on empty stomach, monitor LFTS.

• Antifungals (e.g., Fluconazole):

  • Action: Decreases the release of virus from infected cells.

  • Indication: Influenza A and B.

  • Adverse effects: CNS effects, GI and headache.

  • Misc.: given within 48 hours of flu symptoms or exposure.

• Antivirals for Influenza (e.g., Oseltamivir):

  • Action: Decreases the release of virus from infected cells

  • Indication: Influenza A and B

  • Adverse effects: CNS effects, GI distress, fatigue, dizziness. Headache

• Herpes Antivirals (e.g., Acyclovir, Valacyclovir):

  • action: Inhibits viral DNA synthesis

  • indication: Herpes simplex viruses (HSV-1 and HSV-2), chicken pox, shingles

  • adverse effects: GI distress, headache, kidney dysfunction

  • misc.: Monitor kidney function and blood counts, acyclovir can be topical, or oral or IV

  • Antivirals for HIV (e.g., Zidovudine):

    • Action: Inhibits viral reverse transcriptase enzyme and viral replication

    • Indication: Maternal-fetal HIV transmission prevention

    • Adverse effects: Peripheral neuropathy, GI effects, hypersensitivity.

• Fluconazole:

  • Action: Inhibits fungal cell wall synthesis.

  • Indication: Cryptococcal meningitis, prophylaxis from BMT, radiation therapy

  • Adverse effects: Headache, rash, anemia, liver toxicity, QT prolongation

  • Misc.: Possible drug interactions

• Lipoatrophy

  • Indication: Lipid loss due to chronic use.

• Misc.: Monitor hepatic function with chronic use.

Test your knowledge on antibiotics, including penicillins and their specific applications, actions, and side effects. This quiz covers both the general characteristics and the particular types of penicillin-resistant penicillins. Challenge yourself and ensure you understand the critical aspects of antibiotic therapy.