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111 Cards in this Set
- Front
- Back
Amino-penicillin's uses
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HELPs……..
Infections caused by the following organisms: Haemophilius influenzae E.coli Listeria monocytogenes Proteous mirabilis Salmonella typhi Ampicillin Active against gram +ve and gram - ve organisams |
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Side effect of Ampicillin
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Diarrhea is a side effect
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Antipseudomonal penicillins are used to treat
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pneumonias associated with cystic fibrosis…..DOC (Fluroquinolone e.g. Ciprofloxacin also DOC)
Mechanical ventilation……..For prophylaxis of pseudomonal inf. ----> DOC UTI (if…..caused by E.coli, Pseudomonas, proteus, Kebsiella) It has good activity against Pseudomonas aeruginosa High dose cause bleeding by interfering with platelet function. |
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DOC for pneumonia associated with cystic fibrosis
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Anti pseudomonal PC
(Fluroquinolone e.g. Ciprofloxacin also DOC.) |
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Beta-lactamase/Penicillinase inhibitors:
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Clavulanic acid
Sulbactum Tazobactum |
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what formulations combine a beta-lactam antibiotic with a beta-lactamase inhibitor (beta-lactam antibiotic + beta-lactamase inhibitors)
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Ampicillin-Sulbactam
Ticarcillin-Clavulanic acid Piperacillin- Tazobactam Amoxicillin–Clavulanic acid |
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route of admin. for beta lactamase inhi. and what is the exception?
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All of the beta-lactamase inhibitor combinations except amoxicillin-clavulanic acid are parenteral formulations.
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Penicillins….in Pregnancy
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Ampicillin
Penicillin G penicillin V safe for pregnant women. |
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What is the major antigenic determinent of Pc hypersensitivity?
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The major antigenic determinent of Pc hypersensitivity is its metabolite, penicilloic acid, which reacts with proteins and serve as a hapten to cause an immune reaction.
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Jarisch Herxheimer Reaction
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in the treatment of Syphilis……. Penicillin injected in a secondary syphilitic patient produce fever, exacerbation of lesions and vascular collapse.
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Type of hypersensitivity RXN
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1.IgE mediated- Rapid onset, Anaphylaxis,Angioedema,Laryngospasm.
2.IgM and IgG antibodies fixed to the cells -Vasculitis,Neutropenia, Positive Coombs test. 3.Immune Complex formation- Vasculitis, serum sickness, Interstitial nephritis. 4.T-Cell Mediated---Urticarial and Maculopapular rashes, Stevens-Johnson Syndrome |
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Coombs' test
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The Coombs' test looks for antibodies that may bind to red blood cells and cause premature red blood cell destruction (hemolysis).
Positive Coombs' test means pt have antibodies that act against red blood cells. |
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Positive Coombs' test may be due to:
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Autoimmune hemolytic anemia
CLL Drug-induced hemolytic anemia Erythroblastosis fetalis (hemolytic disease of the newborn) Infectious mononucleosis Mycoplasmal infection Systemic lupus erythematosus Transfusion reaction |
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1st generation cephalosporin uses?
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Acts as Pc G substitutes
Activity includes Gram positive cocci(not MRSA), E.coli,Klebsiella pneumoniae and some proteus species (PEcK). Common use in Surgical prophylaxis. None enter CNS. |
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what is cefazolin and what is it DOC for?
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Cefazolin …DOC for surgical prophylaxis, good penetration into bone.
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3rd generation cephalosporin uses?
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3rd generation Cephalosporins are important in empiric management of Meningitis and Sepsis. since they enter CNS.
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Ceftizoxime uses? family?
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Ceftriaxone(IM) and Cefixime (PO) used in single dose for Gonorrhea.
Cefotaxime-active against most bacteria causing Meningitis. Ceftizoxime is active against B.fragilis. 3rd generation ceph. |
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The treatment of choice for gonorrhea in Pc/Cephalosporin -allergic patients.
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Ofloxacin or ciprofloxacin is the treatment of choice for gonorrhea in Pc/Cephalosporin -allergic patients.
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Organisms NOT covered by
Cephalosporins? |
Organisms NOT covered by
Cephalosporins are “LAME”. Listeria monocytogenes Atypicals(Chlamydia,Mycoplasma) MRSA(Methicillin Resistant Staphylococcus aureus) Enterococci. |
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Cephalosporins side effects?
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Most authorities recommend avoiding cephalosporins in patients allergic to penicillins.
Cefotetan,Cefoperazone,Cefamandole, cause hypoprothrombinemia (anti-vitamin K effect)---- cause bleeding and also disulfiram like interactions with ethanol IV injections-Phlebitis (inflammation of a vein) IM injections-Pain. |
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Meningitis DOC?
if meningitis caused by Listeria DOC? |
Meningitis….. Ceftriaxone is DOC (if meningitis caused by Listeria DOC…ampicillin and st. pneumoniae …Pc G)
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Gonorrhea…… DOC?
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Ceftriaxone(IM) and Cefixime (PO) used in single dose for Gonorrhea…… DOC
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Typhoid fever – DOC?
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Typhoid fever – Ceftriaxone (azythromycin, fluroquinolone..also DOC)
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Gonococcal Urethritis DOC? In case of allergies to this group of drugs?
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Ceftriaxone
Ofloxacin or ciprofloxacin is the treatment of choice for gonococcal urethritis in Pc/Cephalosporin -allergic patients. |
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Non-gonococcal urethritis DOC?
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azithromycin or doxycycline.
(a single dose of azithromycin or a 7-day course of doxycycline. Rates of success with either regimen are around 90%) |
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Carbapenams (imipenam and meropenam) USES
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Wide spectrum that includes:
Gram positive cocci Gram negative rods(Enterobacter,Pseudomonas species) Anaerobes (nocardia and actinomyces) ●Important in hospital agents for empiric use in severe life threatening infections. Imipenam is given with Cilastatin (Imipenam +Cilastatin),which inhibits its rapid metabolism by renal dihydropeptidases. |
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Carbapenams Adverse Effects
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GI distress…..nausea, vomiting, diarrhea
Drug fever(partial cross-allergenicity with penicillins) CNS effects,including seizures Renal dysfunction. Eosinophilia, Neutropenia, Neurotoxicity |
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VANCOMYCIN use
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Gram positive cocci including MRSA(DOC) and
enterococci and Clostridium difficile……DOC |
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antibiotic associated colitis/pseudomembranous colitis TX?
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One of the DOC……in antibiotic associated colitis due to clostridium difficile or staphylococci
(antibiotic associated colitis/pseudomembranous colitis… ……ampicillin, Tc, clindamicin RX…..Vancomycin…may be 1st choice but it is reserve drug. Metronidazole…1st choice) |
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Vanco. enters all tissue except?
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CNS, and bone
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Vanco. Adverse effects
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Ototoxicity (usually permanent)
Hypotension/Shock (due to histamine release) diffuse hyperemia(“Red man syndrome”/Red neck syndrome)…… due to histamine release---if given too rapidly IV nephrotoxicity hypersensitivity reactions. |
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Monobactam
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Monobactam---------Aztreonam:
Mode of Action: Monobactam inhibitor of early step in cell wall synthesis. It is a novel beta lactam antibiotic which is not fused to other ring. It inhibits enterobacteriacea and gram –ve rods, e.g Pseudomonas Has no activity against gram +ve and anaerobes. Resistant to Beta-Lactamases. Use: IV drug mainly used in Hospital acquired infections. No cross allergenicity with penicillins or cephalosporins. |
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Fosfomycin
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AKA Phosphomycin and phosphonomycin
Inhibits initial steps in the bacterial wall synthesis Active against both gram +ve and gram –ve Orally used for UTI Safe in pregnancy |
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Protein synthesis inhibitors
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MCAT
Macrolides (50S) Aminoglycosides (30 S) Chloramphenicol (50S) Tetracyclines (30S) |
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MOA of Aminoglycosides
(30S) |
Interfere with initiation codon functions-block association of 50S ribosomal subunit with mRNA-30S(static);misreading of code- incorporation of wrong AA(cidal).
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Tetracyclines
(30S) |
2.Amino acid incorporation
Block the attachment of aminoacyl tRNA to acceptor site,(static) |
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ChloramPhenicol (50S)
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3.Formation of Peptide bond
Inhibit the activity of peptidyl transferase,(static) |
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Macrolides and Clindamycin
(50S) |
4.Translocation
Inhibit translocation of peptidyl t RNA from acceptor to donor site,(static). |
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Macrolides
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Use as an alternative to Pc in individuals who are allergic to beta-lactam antibiotics.
Antibiotics in this group include: Erythromycin Clarithromycin Azithromycin Oleandomycin Dirithromycin (semisynthetic derivative of erythromycin ) -----is no longer available in the United States |
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Uses of Macrolides
|
is used for the infections caused by
Gram positive cocci (not MRSA) Atypical organisms (chlamydia, Mycoplasma and Ureaplasma species) Legionella pnemophilia Campylobacter jejuni. Syphilis (if allergic to Pc) Corynebacterium diptheriae Use as an alternative to Pc in individuals who are allergic to beta-lactam antibiotics. |
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Azithromycin
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similar spectrum but it is less effective against streptococci and staphylococci than erythromycin, is far more active, especially organisms associated with sinusitis or otitis media (H.influenza, M.catarrhalis)
Erythromycin and azithromycin are excreted primarily in active form in bile, with only low levels found in urine. Mycobacterium avium intracellulare (MAC) |
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Carithromycin:
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Carithromycin has more activity for MAC and H.pylori.
DOC…for MAC(mycobacterium avium intracellular) Clarithromycin is eliminated largely by the kidney |
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Erythromycin Vs. Azithromycin side effects
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rythromycin causes GI distress (via stimulation of motilin receptors)
The estolate form (of erythromycin) is associated with cholestasis and not recommended in Pregnancy or the Elderly. Inhibits P450 drug metabolism(potential drug interactions) Auditory dysfunction at High I.V doses IV administration of erythromycin is associated with high incidence of thrombophlebitis. Azithromycin: Azithromycin is safer in Pregnancy and does not inhibit P450 Drug metabolism. |
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Clarithromycin side effects?
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Clarithromycin causes less GI distress than erythromycin.
It also inhibits P450 drug metabolism (potential drug interactions) Causes Reversible Deafness at high doses Animal studies have shown Teratogenic effects. |
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Clindamycin
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Gram positive cocci(not MRSA) and
anaerobes including B.fragilis. Has also been used in Toxoplasmosis…..DOC osteomyelitis due to Gram positive cocci. First known drug to cause Pseudomembranous colitis (S/A..ampicillin, Tc, clindamycin) (Rx…Vancomicin, Metronidazole) |
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Pseudomembranous colitis TX?
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Vancomicin,
Metronidazole |
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AMAs avoided in Pregnancy
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Aminoglycosides
Erythromycin estolate Clarithromycin Fluroquinolones Tetracyclines Sulfonamides |
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Why anaerobes are resistant to amino-glycosides?
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Aminoglycosides are bactericidal, accumulated intracellularly in microorganisms via an O2-dependent uptake.
Thus Anaerobes are innately resistant. |
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NAme the amino glycosides?
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Streptomycin
Neomycin Kanamycin Gentamicin Tobramycin Amikacin Netilmicin |
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clinical uses of amino glycosides?
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Infection due to Pseudomonas
Chronic UTI Tularemia Pneumonia caused by …….E.coli,Klebsiella Aminoglycosides are often used in combinations. Synergistic actions occur for infections caused by enterococci (with penicillin G or ampicillin) and P.aeroginosa (with an extended spectrum penicillin). |
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Streptomycin is used for?
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Streptomycin is used in Tuberculosis
Bacterial endocarditis Tularemia…..AKA rabbit fever, deer fly fever (Francisella tularensis, gram-negative coccobacillus) Plague (Yersinia pestis, Gram negative ……usually resulting from the bite of an infected flea. The fleas are often found on rodents, such as rats and mice ) Brucellosis One of the DOC for (Bubonic) Plague and Tularemia. |
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Neomycin systemic or tpical use?
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Too toxic for systemic use, is used topically.
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Tularemia TX?
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Streptomycin or gentamicin……… IV
Tetracycline class ( doxycycline) or Fluoroquinolone class (ciprofloxacin) of antibiotics are taken orally. Streptomycin….DOC |
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Dosage of Streptomycin for renal dysfunction?
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Renal elimination is proportional to GFR, and major dose reduction is needed in Renal dysfunction.
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adverse effect of streptomycin?
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Nephrotoxicity includes Proteinuria,Hypokalemia,Acidosis,and Acute tubular necrosis(ATN)……..usually reversible.
Ototoxicity from Hair cell damage; includes Deafness and Vestibular dysfunction……which are not readily reversible. Ototoxicity……may be enhanced by Loop Diuretics. Neuromuscular blockade: may enhance the effects of Skeletal muscle relaxants. Contact dermatitis: By Neomycin |
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CHLORAMPHENICOL
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Is active against a wide range of Gram +ve and Gram
–ve organisms, but because of its toxicity, its use is restricted to life-threatening infections in which there are no alternatives. |
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clinical use of chloramphenicol?
|
Bacteriostatic with a wide spectrum of activity but
currently a back up drug for infections due to……. Salmonella typhi B.fragilis, Rickettsia Bacterial meningitis. ▪Orally effective, with good tissue distribution,including CSF. because of its toxicity, its use is restricted to life-threatening infections in which there are no alternatives |
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metabolization and does consideration for chloramphenicol
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Metabolized by Hepatic glucuronidation
So….. dose reductions are needed in Liver dysfunction and in Neonates. |
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Side effects of chloramphenicol
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Dose-dependent bone marrow suppression is common.
Aplastic anaemia “Gray Baby Syndrome” in neonates (Due to decreased Glucuronysyl transferase). Optic neuritis in children. Inhibits CyP450----->Inhibits metabolism of Phenytoin, Sulfonylureas,and Warfarin --->thus elevating their concentration and potentiating their effects. |
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NAme Bacteriostatic drugs,actively taken up by susceptible bacteria?
MOA? |
MOA: Block the attachment of aminoacyl tRNA to acceptor site.
Tetracycline Chlortetracycline Oxytetracycline Demeclocycline….may cause diabetes incipdus Methacycline Doxycycline….can be used in renal failure Minocycline |
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tetracyclines display broad-spectrum activity and are Effective against?
|
both gram-positive and gram-negative
bacteria, including atypical microorganisms…. Rickettsia Coxiella Mycoplasma Tc.. are also effective in the treatment of brucellosis tularemia infections caused by Pasteurella and Mycoplasma spp. |
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Tetracyclines are still the drugs of choice for treatment of ?
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Tetracyclines are still the drugs of choice for treatment of
Cholera diseases caused by Rickettsia, Coxiella chlamydial diseases (trachoma, lymphogranulomavenereum, and psittacosis ) Nonspecific urethritis --->DOC: Atypical microorganisms |
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Tetracyclines are clinically effective in acne because of?
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their antioxidant effect on the degranulated neutrophils in the comedone acidic contents (in which long-term low-dose therapy is popular).
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which tetracycline is a popular choice for patients with preexisting renal disease or those who are at risk for developing renal insufficiency? why?
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Doxycyclin
The lack of nephrotoxicity is related mainly to biliary excretion, which is the primary route of doxycycline elimination. (S/A…erythromycin and azithromycin) |
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Doxycyclin is DOC for?
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Doxycycline is DOC… anthrax (Bacillus anthracis) after exposure.
Doxycycline is DOC…primary stage of Lyme disease in adults and children older than 8 years. DOC..for chronic/acute Prostatitis because it reaches high levels in prostatic fluid |
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Minocycline appears where?
what is the usage? |
in Saliva at high concentrations and is used in the Meningococcal Carrier State (alternative to rifampin).
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which tetracycline is the most lipid soluble?
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Doxycycline
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Demeclocycline use?
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Demeclocycline is used in Syndrome of inapproriate secretion of ADH (SIADH ….excessive release of ADH)---> Demeclocycline blocks
-> ADH actions in the collecting ducts. |
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Tetracycline's side effects?
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GI distress (this can be avoided if the drug is taken with food other than dairy products ,e.g milk, yogurt)
Superinfections leading to Candidiasis or Colitis. Tooth enamel dysplasia and possible decreased bone growth in children (avoided in Children). Renal dysfunction (Fanconi syndrome) Photo toxicity with Demeclocycline and Doxycycline. Have caused Liver dysfunction during Pregnancy at very high doses(Contraindicated in Pregnancy) Vestibular dysfunction by Minocycline and Doxycycline. Pseudotumor cerebri : benign ICH characterized by headache, and blurred vision |
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C/I of Tetracyclines
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Pregnant or breast feeding women
Children under 8 yrs of age Renal impairment |
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RX for Lyme disease( B. burgdorferi )
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Rx :
Doxycycline ---->DOC If pt is pregnant/age <8 yrs…..then Pc (amoxycillin)………..DOC If allergic to Pc--> erythromycin If pt has= skin rash+7th CN palsy+ arthritis----> doxycycline or amoxycillin If pt has=CVS+CNS symptoms…then--> Ceftriaxone or PcG inj. |
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Quinupristin and Dalfopristin
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Quinupristin and Dalfopristin are Streptogramins that act in concert via several mechanisms.- via 50S
Protein synthesis Inhibitors. |
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Quinupristin and Dalfopristin uses?
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parenterally in severe infections caused by Vancomycin Resistant Staphylococci(VRSA) and Enterococci(VRE) as well as other Drug resistant Gram positive cocci
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Quinupristin and Dalfopristin adverse effects?
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Toxic potential remains to be established.
Resistance has been reported via the formation of inactivating enzymes and increased efflux mechanisms. |
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activity and clinical use of Linezolid
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Linezolid is an oxazoli-di-none that inhibits the formation of the initiation complex in bacterial translation systems by preventing formation of the N-formyl-methionyl-t-RNA-ribosome-mRNA ternary complex
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Linezolid use and side effect?
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A new drug available in oral and parenteral
formulations for treatment of VRSA, VRE(vancomycin-resistant enterococci ) and Drug resistant Pneumococci. Adverse effects: Headache and GI distress |
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Folic acid inhibitors, how they fxn?
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Folic acid coenzymes are required
---- for the synthesis of purines and pyrimidines (precursors of RNA and DNA) and other compunds are required for cellular growth and replication. In absence of folic acid, cells can not grow or divide. Sulfa drugs are inhibitors of folic acid synthesis. |
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Antifolate Drugs?
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1. Inhibitors of dihydropteroate synthetase: Sulfonamides
2. Inhibitors of dihydrofolate reductase: Trimethoprim Pyrimethamine 3. Inhibitors of dihydropteroate synthetase and dihydrofolate reductase: Co-trimoxazole |
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MOA of Sulfonamides?
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All sulfonamides are synthetic strustural analogs of p-aminobenzoic acid (PABA)
Compete with PABA, causing inhibition of Dihydropteroate synthase and formation of non functional folic acid. |
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Sulfonamides are used against which bacteria?
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Sulfonamides inhibit both gram positive and gram-negative bacteria, nocardia, Chlamydia trachomatis, and some protozoa.
Some enteric bacteria, such as E coli, klebsiella, salmonella, shigella, and enterobacter, are inhibited |
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Clinical use of Sulfonamides? and are DOC for?
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Nocardial infections……DOC
Simple Urinary Tract Infections (UTI)…….Sulfisoxazole Ulcerative Colitis….Sulfasalazine..DOC Trachoma….Sulfacetamide,topical Burns……Silver Sulfadiazine, topical Toxoplasmosis-Sulfadiazine+Pyrimethamine…DOC (S/A. Clindamycin) |
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Biodisposition and elimination of Sulfonamides?
|
Effective orally and eliminated via Hepatic metabolism (acetylation) and renally as unchanged drug.
Less water soluble metabolites of the drug……… may cause Crystalluria. Sulfonamides bind to plasma proteins…..increased drug interactions including increased effects of Methotrexate,Phenytoin and Warfarin. |
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Adverse effects of Sulfanamides
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Hypersensitivity, mostly Rashes,which can be Severe (Stevens-Johnson Syndrome….S/A Pc).
cross allergenicity between Sulfonamides and possibly with Sulfonylurea hypoglycemics. GI distress (NVD),Phototoxicity Haemolysis in G6PD deficiency are common. Avoid in third trimester because they cross placental barrier and may displace bilirubin from the plasma proteins in Neonates-------Kernicterus Crystalluria…nephrotoxicity (RX..adequate hydration, alkalinization of urine) |
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Dihydrofolate reductase
inhibitors
Name MOA |
Trimethoprim
Pyrimethamine inhibits bacterial dihydrofolic acid reductase (dihydrofolate reductase). Use in combination with sulfonamide drugs 1st combination : Trimethoprim +Sulfamethoxazole combination ----called Co-trimoxazole 2nd combination : Pyrimethamine + Sulfadiazie |
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Trimethoprim
Pyrimethamine are used as combination with what drugs and why? |
When Trimethoprim is used with Sulfamethoxazole (TMP-SMX),there is synergism and decreased emergence of resistance resulting from the sequential blockade of Folic acid synthesis.
the combination used usually is Bactericidal. 2nd combination : Pyrimethamine inhibits Dihydrofolate Reductase in Toxoplasma gondii and is used with Sulfadiazine in prophylaxis and treatment of Toxoplasmosis. Pyrimethamine + Sulfadiazine ………prophylaxis and treatment of Toxoplasmosis. |
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Co-trimoxazole…clinical uses ?
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Possible co-DOC in complicated UTI and in Respiratory,Ear and Sinus infections associated with H.influenzae, M.catarrhalis.
Backup drug for L.monocytogenes, Proteus mirabilis, S.typhi, MRSA, and Vibrios. DOC for prophylaxis and treatment of Pneumocystis carinii Pneumonia (PCP) |
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Trimethoprim may cause what adverse effects?
|
Megaloblastic anaemia
Leukopenia (Rx…Leucovorin) Thrombocytopenia Haematotoxicity, Drug fever,Rashes and severe GI distress are problematic in patients with AIDS. |
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Inhibitors of nucleic acid metabolism?
|
The quinolones/FQ classified into:
1st generations: older Nalidixic acid Cinoxacin FLUOROQUINOLONES 2nd generations: Norfloxacin Ciprofloxacin, Ofloxacin Enoxacin, Lomefloxacin 3rd generations: Levofloxacin Sparfloxacin Gatifloxacin; 4th generations: Trovafloxacin Moxifloxacin. Several of the newer quinolones have been recently removed from the market as a result of QT prolongation |
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Fluoroquinolones MOA?
|
The Fluoroquinolones are Bactericidal
They interfere with Bacterial DNA synthesis. They inhibit Topoisomerase 2 (DNA gyrase), blocking the relaxation of supercoiled DNA, required for replication. Also inhibit Topoisomerase 4, responsible for separation of replicated DNA during cell division. |
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Fluoroquinolones clinical use?
|
Wide spectrum that includes
Gram positive Gram negative Cocci, Gram negative rods (E.coli,S.typhi, Shigella,Serratia etc.) some anaerobes (C.jejuni) Mycobacteria. Active when administered orally (inhibited by Antacids) and have a wide tissue distribution including Bone. FQs may have enhanced activity against resistant Pneumococci …..Sparfloxacin resistant Chlamydia……Ofloxacin |
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Fluroquinolones are DOC for?
|
Ciprofloxacin and Ofloxacin are co-DOC for Gonorrhea(single doses) but Ceftriaxone….DOC 1st choice.
DOC for…complicated/recurrent UTI (3rd gen cephalosporin can be used after having C/S report) (for uncomplicated/simple UTI..Sulfonamides or Amoxicillin or 1st gen cephalosporin) |
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C/I to Fluroquinolones
|
GI distress(NVD), Rash, Phototoxicity (especially sparfloxacin).
CNS effects usually mild (insomnia,dizziness and headache),but seizures occur in overdose and in susceptible patients. Contraindicated in Pregnancy and Children, based on animal studies showing effects on collagen metabolism and cartilage development;tendonitis(and tendon rupture) has occurred in adults. |
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Drug specific toxicity of Sparfloxacin?
|
Increases Q-T interval
|
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Drug specific toxicity of Trovafloxacin?
|
Hepatotoxicity
|
|
The primary/1st line drugs in combination
regimens for TB treatment are : |
Isoniazid (INH)..most potent anti-TB drug, bacteriostatic
Rifampicin…..bactericidal Ethambutol Pyrazinamide Regimens may include two to four of these drugs, but in the case of highly resistant organisms, other agents may also be required. |
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Backup/2nd line drugs for treatment of TB include:
|
Backup/2nd line drugs include:
FAACCE Aminoglycosides (streptomycin, amikacin, kanamycin) Aminosalicylic acid : competitive inhibitor for PABA Fluroquinolones Capreomycin (marked hearing loss) Cycloserine (Neurotoxic) Ehtionamide : analog of INH |
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Drugs For prophylaxis of TB?
|
For prophylaxis of TB:
Usually INH, But Rifampicin if intolerant to INH. In suspected drug resistance, both drugs may be used in combination. |
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Prophylaxis and RX of Mycobacterium Avium Intracellulare (MAC)
|
For Prophylaxis:
Azithromycin or Clarithromycin For Rx: Clarithromycin+Ethambutol+Rifabutin (an analog of Rifampicin) |
|
Isoniazid
MOA |
Inhibits mycolic acid synthesis;
high level of resistance… deletion in cat K gene (codes for catalase). |
|
Isoniazid
Adverse effects |
Hepatitis,
Peripheral neuritis (use Vit B6), Haemolysis in G6PDdeficiency, SLE in Slow acetylators. |
|
Rifampicin use
|
Also used for Leprosy, prophylactically household members exposed to meningitis caused by for meningococci, H.influenzae
|
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Rifampicin MOA
|
Inhibits DNA dependent RNA polymerase.
|
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Rifampicin adverse effect
|
Proteinuria,
Hepatitis, “Flu like Syndrome” Induction of P 450, Thrombocytopenia, Red orange metabolites. |
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Ethambutol MOA
|
Inhibits synthesis of arabinogalactan (cell wall component)
|
|
Ethambutol adverse effects
|
Dose dependent Retrobulbar neuritis--->decreased visual acuity and Red –Green discrimination
|
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Pyrazinamide adverse effects
|
Polyarthralgia,Myalgia, Hepatitis,Rash,
Hyperuricemia(#1 side effect) Phototoxicity, increased porphyrin synthesis. |
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Streptomycin adverse effects and MOA
|
Deafness(*)
Vestibular dysfunction Nephrotoxicity(*) MOA: Protein syn.Inhibition |
|
define:
Multi-drug-resistant tuberculosis (MDR-TB) Extensively drug-resistant TB (XDR-TB) |
Multi-drug-resistant tuberculosis (MDR-TB):
is defined as resistance to the two most effective first-line TB drugs: rifampicin and isoniazid. Extensively drug-resistant TB (XDR-TB) : is also resistant to three or more of the six classes of second-line drugs. |
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Chemotherapy for leprosy?
|
Triple drug regimen:
Dapsone Clofazimine Rifampicin/Rifampin |
|
Dapsone is used for?
S/E are? |
Dapsone: structrually related to sulfonamides.
Use Rx: Leprosy, PCP S/E: hemolysis in pt with G6PD deficiency, methemoglobinemia, peripheral neuropathy. |
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Clofazimine use?
|
Clofazimine is indicated in the treatment of lepromatous leprosy, including dapsone-resistant lepromatous leprosy and lepromatous leprosy complicated by erythema nodosum leprosum.
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