Bactericidal inhibitors of bacterial protein synthesis Flashcards
Aminoglycosides types
- gentamicin
- tobramicin
- bactericidal inhibitors of protein synthesis–> concentration dependent agents (require a certain concentration to be reached in order to have full effect)
aminoglycosides uses
1) GRAM - (CRE)
2) severe gram - infections (multi drug resistant organisms)
3) some pre op
- Gram + and Gram -
aminoglycosides US boxed warnings
1) nephrotoxicity- irreversible
2) ototoxicity - typically irreversible (ppl with renal dysfunction are more susceptible to this)
3) pregnancy- fetal harm
- these kind of limit use
MOA of aminoglycosides
inhibits bacterial protein synthesis
bactericidal
Routes of aminoglycosides
IV (can use IV formulation for inhalation for tobramycin- cystic fibrosis patients)
Metabolism/ excretion of aminoglycosides
pharmacy to dose- peaks for concentration dependent killing, troughs to minimize toxicity
Rare affect of aminoglycosides
aminoglycoside induced neuromuscular blockade –> paralyzes patients
Antimetabolites (2)
1) sulfonamides
2) trimethoprim
Sulfonamides (1)
sulfamethoxazole / trimethoprim (bactrim)
- inhibit folic acid synthesis
-antimetabolites
sulfonamide uses
cellulitis, uti, Gram +, good MRSA coverage
MRSA, MSSA, Gram +
sulfonamide MOA
inhibit folic acid synthesis
- trimethoprim combined with this inihibits folic acid synthesis via a different pathway
sulfonamide Contradindications
history of drug induced immune thrombocytopenia
ADR of sulfonamide
1) hyperkalemia (blocks Na channels in the distal nephron, inhibits potassium secretion, potentially fatal)
2) hypersensitivity reaction - delayed and immediate
- immediate- typical rash, angioedema, anaphylaxis
- delayed - stevens johnson syndrome , toxic epidermal necrolysis (severe forms of rashes)
metabolism/excretion sulfonamide
Renal adjusment needed
Sulfacetamide
topical for acne, bacterial infections, scaling dermatoses, ophthalmic infections
Silvadene
silver sulfadiazine - topical for burn treatment- prevention and treatment of wound sepsis
sulfadizine
toxoplasmosis treatment - first line
Fluoroquinolones indications
- broad spectrum –> cover GRAM + and atypical organisms
- MOXIFLOXACIN (BROADEST) –> ANAEROBES
- do not cover MRSA
- Levofloxacin (levaquin)/ moxifloxican –> respiratory Fluoroquinolones
- Ciprofloxacin (CIPRO) –> non-respiratory Fluoroquinolones (belly button down)
-gram +, gram -, pseudomonas, atypicals and moxifloxacin does anaerobes, some MSSA
US box warnings Fluoroquinolones
1) serious adverse reactions –> tendinitis and tendon rupture, peripheral neuropathy, CNS effects
2) Exacerbation of myasthenia gravis –> avoid in patients with MG
MOA Fluoroquinolones
Promotes DNA strand breakage via inhibition of topoisomerase
Routes of Fluoroquinolones
Oral (xr tablets/ solution)
IV
ophthalmic/otic
Metabolism/excretion Fluoroquinolones
- require renal adjustment
- absorption decreased by POSITIVE CATIONS (2 hours before or 6 hours after)
Fluoroquinolones ADRs (severe)
1) CNS effect/neuroexcitation
2) QT interval prolongation
3) tendon rupture/ tendinopathy
4) phototoxicity
Metroidazole (flagyl) Indications
Anaerobic bacterial infections (bacterial vaginosis), trichomoniasis, surgical prophylaxis
- THE BEST ANAEROBIC AGENT
US boxed warnings Metroidazole (flagyl)
carcinogenic in mice and rats
Contraindications of Metronidazole (flagyl)
- first trimester pregnancy
- ***alcohol-disulfiram reaction **: bad to have alcohol with this drug. If you consume alcohol with this it will form a chemical bond that induces vomiting
Routes of Metroidazole (flagyl)
- oral tab
- iv solution
- vaginal cream
ADR Metronidazole (flagyl)
- nausea and headache
- metallic taste!!!! –> can linger for a long period of time
metabolism/secretion of Metroidazole (flagyl)
hepatic adjustment –> reduce dose by 50% in severe liver impairment
Rifampin Indications
TB, meningiococci elimination from nasopharynx
- alot of off label uses
- Gram +, Gram -, MSSA
- usually develops resistance if used alone
MOA Rifampin
inhibits RNA synthesis (blocks transcription via DNA dependent RNA polymerase
Contraindications Rifampin
- concurrent use of HIV and Hep C drugs
- MANY DRUG INTERACTIONS (strong inducer of CYP3a4 and other CYPS
ADR Rifampin
discolors body fluids- red/ orange color
Metabolism/ excretion Rifampin
no dosage adjustments
Nitrofurantoin (MACROBID AND MACRODANTIN) Indications
UTIs and prophylaxis for recurrent UTIs
- Gram +, Gram -, MSSA
Nitrofurantoin (MACROBID AND MACRODANTIN) MOA
inhibits protein, DNA, RNA and cell wall synthesis
Nitrofurantoin (MACROBID AND MACRODANTIN) Contraindications
anuria, oliguria, or significant impairment of renal function, previous history of cholestatic jaundice or hepatic dysfunction with prior use
Nitrofurantoin (MACROBID AND MACRODANTIN) ADR
well tolerated
