Infection 2 - Antimicrobials Flashcards
Which antibiotics inhibit cell wall synthesis?
- Beta-lactams
- Glycopeptides
Which antibiotics inhibit protein synthesis?
- Tetracyclines
- Macrolides
- Aminoglycosides
Which antibiotics inhibit nucleic acid synthesis?
Quinolones
What is the mechanism of action of Beta-lactams?
Inhibit cell wall synthesis:
- Express beta-lactamase genes
- Prevents peptidoglycan crosslinking
What are the 4 main classes of Beta-lactams?
1) Penicillins
2) Cephalosporins
3) Carbapenems
4) Monobactams
What type of antibiotic would you use to treat Streptococcus?
- Penicillin
- Meropenem
- Tetracycline
Which antibiotics make up the triple therapy given for Helicobacter pylori (with proton pump inhibitors)?
1) Amoxicillin
2) Clarithromycin
Which types of penicillin are active against most gram positives and negatives, and anaerobes?
- Co-Amoxiclav
- Tazocin
Which cephalosporin is used against Neisseria meningitidis and gonorrheoa?
Ceftriaxone
What type of antibiotic are cephalosporins?
Beta-lactam
What type of antibiotic are penicillins?
Beta-lactam
What type of antibiotic are carbapenems?
Beta-lactam
What type of antibiotic are monobactams?
Beta-lactam
Name a carbapenem:
- Meropenem
- Imipenem
Name a monobactam:
Aztreonam
What is the mechanism of action of glycopeptides:
Inhibit cell wall synthesis:
- prevents peptidoglycan incorporation
What makes vancomycin a better antibiotic than penicillin?
Vancomycin has a lipid target, whereas Penicillin has a protein target.
Proteins are more variable and more likely to mutate, making antibiotic resistance against penicillin more likely.
What types of bacteria are glycopeptides (ie vancomycin) active against?
Most gram positive bacteria
What antibiotic would you use to treat a severe Clostridium difficile infection?
Vancomycin
Name 2 glycopeptides:
- Vancomycin
- Teicoplanin
What is the mechanism of action of tetracyclines?
Inhibit protein synthesis:
- Inhibit translation by preventing amino acyl tRNA’s from associating with the ribosomes
Which antibiotics would you use against MRSA?
- Vancomycin
- Clarithromycin
What type of antibiotic is often used against Chlamydia/Acne/Rosacea etc?
Tetracycline
What is the mechanism of action of aminoglycosides?
Inhibit protein synthesis:
- Bind to 30s ribosome
What type of bacteria are aminoglycosides active against?
Mostly gram negative
Name 2 types of aminoglycosides:
- Nitrofurantoin
- Gentamycin
What type of antibiotics would you use against UTIs?
- Nitrofurantoin
- Trimethoprim
What are the drawbacks of using gentamycin?
- Narrow therapeutic window
- Nephrotoxic
- Ototoxic
Which antibiotic is only used for severe gram negative sepsis?
Gentamycin
What is the mechanism of action of macrolides?
Inhibit protein synthesis
Name 3 macrolides:
1) Erythromycin
2) Clarithromycin
3) Azithromycin
What type of antibiotic would you use against Legionella pneumophila?
Erythromycin
What type of antibiotic is often used for skin or upper respiratory tract infections?
Macrolides: Erythromycin/Clarithromycin/Azithromycin
What is the mechanism of action of quinolones:
Inhibit nucleic acid synthesis
- Inhibit DNA gyrase
Name a quinolone:
Ciprofloxacin
What type of bacteria is ciprofloxacin active against?
Gram negative bacteria
What type of antibiotic prevents folic acid synthesis?
Dihydrofolate Reductase Inhibitors
- Trimethoprim
- Co-Trimoxazole
What are the 2 main classes of antifungals?
1) Azoles
2) Polyenes
Name 2 types of Azoles:
- Fluconazole
- Itraconazole
- Voricanazole
- Posaconazole
What type of antibiotic would you use against Candida albicans?
- Nystatin (topical)
- Fluconazole (oral)
Name 2 types of polyenes:
1) Nystatin
2) Amphotericin
What antibiotic would you use against Chlamydia?
- Azithomycin
- Tetracycline
Name the antiviral active against Influenza A + B:
Oseltamivir ‘Tamiflu’
What is Aciclovir used for?
- Herpes simplex virus (genital herpes, encephalitis)
- Herpes varicella zoster virus (Chickenpox, shingles)
Name an antiprotozoal, which is also active against anaerobic bacteria:
Metronidazole
What is Metronidazole used for?
- Clostridium difficile
- Bacterial vaginosis
- Ameobiasis
- Giardiasis
- Trichomoniasis
Which antibiotic is used against herpes infections? (simplex and varicella zoster)
Aciclovir
