40 Questions
What is the primary reason for using drug combinations in antibiotic therapy?
To decrease the risk of emergence of resistant organisms
What is the primary consideration when determining the necessity of antibiotic treatment?
The potential risk of detrimental effects to the patient's life
What is the mechanism of resistance in β-lactamase resistant organisms?
Enzymic inactivation
What is the advantage of combining bactericidal and bacteriostatic agents?
No advantage, it is ineffective
Which of the following pharmacological sanctuaries is characterized by poor penetration of antibiotics due to the presence of a natural barrier?
Blood-brain barrier
What is the primary difference between bacteriostatic and bactericidal antibiotics?
The mechanism of action against bacteria
What is the primary mechanism of drug resistance due to spontaneous mutation?
Genetic alteration
Which of the following antibiotic characteristics is defined as the lowest concentration of an antimicrobial that will inhibit the visible growth of a microorganism?
MIC
What is the classification of antibiotics based on their mechanism of action?
Bactericidal vs. bacteriostatic
What is the common complication of antibiotic therapy due to high levels in serum?
Direct toxicity
What is the primary goal of pulsed dosing in antibiotic treatment?
To interval dose in escalating levels past the MIC early on in treatment
What is the characteristic of natural antibiotics?
They are metabolic by-products of soil microorganisms
Which of the following antibiotics is classified as a Category A drug in terms of fetal risk during pregnancy?
Azithromycin
What is the primary factor to consider when selecting an antibiotic treatment option based on cost?
The effectiveness of the drug against the specific type of bacteria
What is the primary disadvantage of combining antibiotics?
Increased risk of superinfection
Which of the following antibiotics is characterized by time-dependent killing?
Beta-lactams
What is the primary mechanism of action of β-lactam antibiotics?
Inhibition of cell wall synthesis by inactivating transpeptidases
Which of the following β-lactam antibiotics is not classified as a semisynthetic penicillin?
Ceftriaxone
What is the mechanism of action of ß-lactamase inhibitors?
Inactivating ß-lactamases by a 'suicide' mechanism
What is the primary target of β-lactam antibiotics in the bacterial cell?
Transpeptidases
Which of the following antibiotics inhibits protein synthesis by binding to the 50s ribosomal subunit?
Erythromycin
What is the mechanism of action of glycopeptides?
Inhibiting the assembly of the murein monomer into peptidoglycan
Which of the following is a characteristic of carbapenems?
Broad spectrum of activity, IV administration
What is the effect of azithromycin on Haemophilus compared to erythromycin?
It has better activity against Haemophilus
What is the mechanism of action of penicillin on transpeptidases?
Formation of a penicilloic-enzyme complex
Which of the following generations of cephalosporins includes Cefotaxime?
Third generation
What is the difference in the excretion of clarithromycin and azithromycin?
Clarithromycin is excreted biliarily, while azithromycin is excreted both biliarily and renally
What is the primary effect of β-lactam antibiotics on bacterial growth?
Inhibition of cell wall synthesis
What is the effect of clindamycin on the production of toxins by GAS?
It inhibits the production of toxins
What is the mechanism of action of clindamycin?
It inhibits protein synthesis by binding to the 50s ribosomal subunit
Which of the following β-lactam antibiotics is used to treat severe infections of resistant bacteria?
Ertapenem
What is the effect of erythromycin estolate on the liver?
It causes cholestatic hepatitis
What is the primary mechanism of action of aminoglycosides against gram(-) bacilli and staphylococcus species?
Inhibiting the binding of tRNA to the 30S ribosomal subunit
Which of the following antibiotics is bactericidal against pneumococci, GAS, and anaerobes?
Linezolid
What is the primary mechanism of action of fluoroquinolones against gram-negative bacteria?
Acting on enzymes topoisomerases II (DNA gyrase) in gram-negative bacteria
What is the primary mechanism of resistance to tetracyclines in bacteria?
All of the above
What is the primary mechanism of action of sulfonamides against bacteria?
Competitively incorporating into tetrahydropteroic acid
What is the primary mechanism of action of metronidazole against anaerobic bacteria?
Generating metabolites that are toxic to bacteria
What is the primary mechanism of resistance to aminoglycosides in bacteria?
All of the above
What is the primary mechanism of action of clindamycin against staphylococci, streptococci, anaerobes, and H. pylori?
Concentration-dependent bactericidal activity
Test your knowledge on the considerations for antibiotic treatment, including the ideal treatment approach, empirical therapy, and determining the necessity of starting treatment before ID and sensitivity is determined.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
