lecture 5 Flashcards
What are the fluroquinolones
Ciprofloxacin
Delafloxacin
Gemifloxacin
Levofloxacin
Moxifloxacin
Ofloxacin
What are the inhibitors of folate synthesis
Mafendie
Silver sulfadiazine
Sulfadiazine
Sulfasalazine
What are the inhibitors of folate reduction
Pryimethamine
Trimethroprim
What are the combinations of inhibitors of folate synthesis and reduction
Cotrimoxazole
What are some urinary tract antiseptics
Methenamine
Nitrofurantoin
What are quinolomas
Examples
Function
Mechanism
Examples: Ciprofloxacin, levofloxacin, moxifloxacin and Norfloxacin.
Function; They Inhibit enzymes for bacterial DNA synthesis
- DNA gyrase
- Topoisomerase IV
Mechanism: inhibition of prokaryotic topoisomer ace II, and topoismerase IV causes super coiling and formation of double stranded breaks and then inhibition of DNA and replication and transcription
Quinolomas: bacterial topoisomerase enzymes
DNA gyrase: introduces double stranded breaks, repairs break
Topoisomerase IV: separates daughter chromosomes
Decantenation: unlinking of chemical elements within a ring or chain from each other.
Inhibition -> DNA Damage -> cell death
Quinolomes resistance mechanism and clinical uses
Any alterations to DNA gyrase and tropoisomerase IV, alteration in cell permeability and efflux of drug.
Clinical uses in adults: UTIs, pneumonia, abdominal infections
Quinolomes different types and details please
Norfloxacin: gram negative, nalidixic acid
Ciprofloxacin: some gram positive, very good gran negative, reliable pseudomonas coverage, used for UTIs, GI infections, ear drops for otitis external
Levofloxacin: more gram positive, better strep pneumo coverage then cipro, less active against pseudomas, used for pneumonia
Gatifloxacin, sparfloxacin, moxifloxacin: less effective for pseudomonas, also used for pneumonia, gram +
Flashcard on slide 12 please
Quinolones adverse effects
Gastrointestinal upset: anorexia, vomiting, nausea
Neurological side effects: headache, dizziness,
QT prolongation on EKG due to blockade of K+ channels can lead to torsade de pointes
Tendon rupture: common in older patients on steroids
We can NOT use in pregnancy or children as it is toxic when developing cartilage
Fluoroquinolones
Examples
Mechanism
Use
Adverse effectes
Resistance
Example: Ciprofloxacin, ofloxacin, respiratory fluoroquinolones, Levofloxacin, moxifloxacin
Mechanism: inhibits prokaryotic enzyme Topoisomerase II and IV.
Clinical: gram - rods
What is the function of the topoisomerase enzyme
To prevent supercooling or tangling of DNA. Some cleave the chains of DNA.
What happens if we block the topoisomerase enzyme
We have DNA gyrase and topoisomerase IV, if we block them we can no longer prevent supercooling so we will have double stranded breaks as topoisomerase usually helps with resealing so without it we have breakage
What drugs block the topoisomerase IV and DNA gyrus
All the floxacin.
The ciprofloxacin, levofloxacin, moxifloxacin and norfloxacin.
Which bacteria are atypical that causes pmeumonia
Micro plasma, legionella and chlamydia
What is doxycycline
Protein synthesis inhibitor
What drugs are used to treat respiratory tract infections and GI and aerobic infections
And what are the side effects
And the mechanism
The fluroquinolomas like ciprofloxacin, ofloxacin, respiratory, levofloxacin and moxifloxacin
Side effects: GI upset, headache, dizziness
The drug can block potassium channels in the blood, causing arrhythmia. It also effects the tendons and the cartilage
We can NOT use this drug on children under 18 and pregnant women as it is toxic to cartilage.
Mechanism: inhibits prokaryotic enzymes topoisomerase II and topoisomerase IV. Also blocks gram negative rods of urinartt and GI tracts and some gram positive (otitis externa)
What does ciprofloxacin inhibit
Cytochrome P-450
