Antibiotics Flashcards
Aminoglycoside names and related toxicity
-Gentamicin and streptomycin–>ototoxic
Neomycin
Nephrotoxic
Ototoxic
Neuromuscular blockers
‘
Teratogenic**
Aminoglycoside pathogenesis
-Mutation?
-Needs energy to get inside cell,work better in GRAM- aerobic bacteria (thinner wall and has energy).
-Binds irriversible to 30S subunit, depending on concentration is Bacteriocidal or Bacteriostatic.
-Pumps
What other drug helps efficacy of Aminoglycosides?
-Used?
-Beta lactam–>destroy cell wall and promote entry.
-**Used:Infective Endocartitis with Enteroccoci. **
What drug giving together with Gentamycin + Streptomycin will worsen toxcicity?
-Loop Diuretics (ototoxicity).
What drugs if given with Neomycin will worsen toxicity?
-Amphotericin B, Cisplatin, Vancomycin
Fluoroquinolones names
-Ciprofloxacin, Ofloxacin,Levofloxacin..
Fluoroquinolone mechanism action
-Inhibit Topoisomerase 2 and Top.4–>Bactericidal.
-Mayorly used for UTI (commonest is GRAM-)
A.E Fluoroquinolones:
-Damages cartilage (pregnancy and <18 don’t give), Tensonitis (athletes, >60 yrs.)
-Also during breasfeeding
Ciprofloxacin type of drug and Cyt inhb.?
-Cyt P450 inhb. and Fluoroquinolone.
How do you get resistance towards Fluoroquinolones
-Topoisomeras mutations.
-Praziquantel use for?
and mechanism action?
-Praziquantel (Incr. Ca2+ permeability, Incr. vacuolization)
- Helminths infections (T.Soleum and Schistosoma–>bladder cancer)
Nystatin
-Same as amphotericin B.Topical use only as to otoxic for systemic use or oral candidiasis (thrush); topica for diaper rash or vaginal candidiasis.
Vancomycin mechanism action
-Toxicity
-By-passes acting on PBP,therfeore mutation will not affect it.
-Acts on Glycoproteins chains–>prevents linkage by PBP.
-Nephrotoxic, and vancomycin reaction (massive flushing)
How do you prevent vancomycin infusion reaction?
-Give **ANTI-Histamine. **
Disulfiram reaction ass with what drug and what it is?
Chephalosporins ,1* generation sulfonylureas, Procarbazine, Griseofulvin and Metronidazole
when you use alcohol with chephalosporin–>nausea,flushing and tachycardia.
Sulfonamides (Sulfamethoxazole) mechanism and A.E?
-Binds to bacteria Dihydropteroate Synthase (decr THF=Folate–>needed for DNA synthesis)
-A.E Hemolytic anemia G6PD defc.Photosensitivity,displaces warfarin from albumin,P450 inhb.
Trimethropin actions and A.E?
-Inhb DihydroFolate Reductase
-Used:UTI’s, Shigella<Pneumocystis Jirovecci,Toxoplasmoxis prophylaxis,MRSA.
A.E:Bone Marrow supression–>**Pancytopenia **(megaloblastic anemia),Teratogenic
What drug you give to avoid A.E of Trimetropin?
Leucovorin (Folic acid)
SMX-TMP are and why
-Synergistic and both inhibit folate synthesis.
Macrolides
Clarithromycin,Erythromycin,Azithromycin
-Binds 50S REVERISBLY (BACTERIOSTATIC)–>Blocking translocations.
-Resitance:Efflux proteins.
Erytromycin and Clarithromycin:P450 inhb.
antibiotics that contraindicated in pregnancy?
tetracyclines Aminoglycosides Fluoroquinolones
Give macrolides or doxycycline
Treats anaerobic infections above the diaphragm.
Anaerobic infections (eg,Bacteroides spp.,Clostridium perfringens)
AE:Pseudomembranous colitis (C difficile overgrowth),fever,diarrhea
Clindamycin
-Blocks peptide transfer (translocation) at 50S ribosomal subunit. Bacteriostatic.
What drug is ineffective against mycolic acid bacteria?
-Beta lactam, this bacteria have NO cell wall.
