Maryville Pharm 615 exam 2 |231 Questions and Answers(A+ Solution guide)

Who discovered the first antibiotic? - Alexander Fleming in 1928 What is the leading cause of antibiotic resistance? - Excessive and inappropriate use of antibiotic agents. What are risk factors for having a drug-resistant pathogen? - The leading risk factors include recent use of antibiotics, age younger than 2 or older than 65, day-care center attendance, exposure to young children, multiple medical comorbidities, recent hospitalization, and immunosuppression. How many antibiotic classes are affected by bacterial resistance? - Every antibiotic class. Penicillins - are characterized chemically by the 6-aminopenicillanic acid joined to the beta-lactam ring. What are the four penicillin subclasses? - (1) penicillinase-sensitive or natural penicillins, (2) aminopenicillins, (3) penicillinase-resistant or anti-staphylococcal penicillins, and (4) anti-pseudomonal or extended-spectrum penicillins. How do penicillins hinder bacterial growth? - by inhibiting the biosynthesis of bacterial cell wall mucopeptide (also called murein or peptidoglycan). What do penicillins bind to? - the cell wall during the terminal stages of cell wall formation. During what point are penicillins most effective? - during active cellular multiplication. Lower drug concentrations may result in bacteriostatic effects only. What has reduced the breadth of organsims that penicillin can treat? - penicillinase-producing organisms.What is the only natural penicillin commercially available? - penicillin. What is penicillin (naturally occurring type) active against? - aerobic, gram-positive organisms. Name aminopenicillins. - ampicillin and amoxicillan. What are aminopenicillins active against? - gram-positive organism, and greater activity against gram-negative bacteria because of their enhanced ability to penetrate the outer membrane of these organisms