PBL pharmacology Flashcards
Fluoroquinolones (Ciprofloxacin, norfloxacin, levofloxacin, ofloxacin, moxifloxacin, gemifloxacin, enoxacin) MOA
Inhibit prokaryotic enzymes topo II (DNA gyrase) and topo IV. Bactericidal. Do NOT take with antacids.
Fluoroquinolone clinical use
G- rods of urinary and GI tracts and some G+ organisms. Pyelonephritis (1st line treatment).
Fluoroquinolone toxicity
GI upset, superinfections, skin rashes, HA, dizziness. Can cause leg cramps and myalgias. Contraindicated in pregnant/nursing mothers and children under 18. Can damage tendons.
Fluoroquinolone mechanism of resistance
Chromosome encoded mutation in DNA gyrase, plasmid-mediated resistance, efflux pumps
Trimethoprim MOA
Inhibits bacterial dihydrofolotate reductase. Bacteriostatic. Use with sulfonamide.
Trimethoprim clinical use
In combo with sulfonamides, causing sequential block of folate synthesis. Combination used for UTIs (pyelonephritis only if susceptible), pneumonia treatment and prophylaxis.
Trimethoprim toxicity
Megaloblastic anemia, leukopenia, granulocytopenia.
Sulfonamides (sulfamethoxazole, sulfisoxazole, sulfadiazine) MOA
Inhibits folate syntheses. PABA antimetabolites inhibit dihydropteroate synthase. Bacteriostatic. Bacteriocidal when used with trimethoprim.
Sulfonamide clinical use
G+ and G-. UTI treatment with trimethoprim or just SMX with simple UTI
Sulfonamide toxicity
Hypersensitivity reactions, hemolysis if G6PD deficient, nephrotoxicity, photosensitivity, kernicterus in infants.
Sulfonamide mechanism of resistance
Altered enzyme, decreased uptake or increased PABA synthesis.
Ceftriaxone MOA
3rd generation cephalosporin. Inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins (PBPs) which inhibits the final transpeptidation step of peptidoglycan synthesis in bacterial cell walls. Inhibiting cell wall biosynthesis.
Ceftriaxone clinical use
Can be given to treat pyelonephritis if the fluoroquinolone resistance of E. Coli is greater than 10%.
Aminoglycoside (Gentamicin, neomycin, amikacin, tobramycin, streptomycin) MOA
Bactericidal. Irreversible inhibition of complex by binding 30S subunit. Can cause misreading of mRNA. Block translocation. Require O2 for uptake. Ineffective against anaerobes.
Aminoglycoside clinical use
Treat pyelonephritis if fluoroquinolone resistance of E coli greater than 10%
First line empiric treatment for uncomplicated cystitis
Nitrofurantoin or Trimethoprim/Sulfamethoxazole or fosfomycin
Fosfomycin MOA
Phosphoric acid derivative, inhibits bacterial wall synthesis (bactericidal) by inactivating the enzyme, pyruvyl transferase, which is critical in the synthesis of cell walls by bacteria
Fosfomycin clinical use
Cystitis
Nitrofurantoin MOA
Reduced by bacterial flavoproteins to reactive intermediates that inactivate or alter bacterial ribosomal proteins leading to inhibition of protein synthesis, aerobic energy metabolism, DNA, RNA, and cell wall synthesis. Nitrofurantoin is bactericidal in urine at therapeutic doses.
Nitrofurantoin clinical use
UTI treatment (not pyelonephritis) and acute cystitis
First line treatments for pyelonephritis
Fluoroquinolones unless resistance greater than 10% (than use ceftriaxone or aminoglycoside). Can use Trimethoprim-Sulfamethoxazole if susceptible
Rapid acting insulin (names, onset, time to peak effect, duration of action)
- -Can be taken immediately before a meal
- -Onset: 10-30 min
- -Time to peak effect: 30-60 min
- -Duration of action: 3-5 hours
- -Names: Aspart, lispro, glulisine
Regular (short) acting insulin
- -Onset: 30-60 min (U-100), 30 min (U-500)
- -Time to peak effect: 1.5-2 hrs (U-100), 4-8 hrs (U-500)
- -Duration of action: 5-12 hrs (U-100), 14-15 hrs (U-500)
- -Names: Humulin R and Novolin R (U-100), Humulin R (U-500)
NPH (intermediate) insulin
- -Onset: 1-2 hours
- -Time to peak effect: 4-8 hours
- -Duration of action: 10-20 hours
- -Names: Humulin N, Novolin N (insulin isophane suspension)