Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
85 Cards in this Set
- Front
- Back
What are Antibioitcs ? |
Antibiotics are the molecules that kill, or stop the growth of microorganisms. |
|
What are the characteristics of Gram (+ve) Bacteria?
|
1) Gets dyed Purple with gram stain 2) Has a thick peptidoglycan layer (50-100 layers thick) 3) Cell wall has Teichoic Acid |
|
What are the characterissitcs of Gram (-ve) Bacteria?
|
1) Gets dyed Pink with gram stain 2) Less prominent Peptidoglycan layer (1-2 layers thick) 3) Has porins in the outer membranes 4) Has Periplasmic Space 5) Has a lipopolysaccarhide layer |
|
What are Toxins?
|
Proteins (i.e. effectors) injected into target host cells allowing bacteria to persist and cause disease. |
|
What are th two categories of Toxins?
|
Exotoxins and Endotoxins
|
|
Define Broad Spectrum Antibiotic
|
Antibiotics that can kill or inhibit a wide range of Gram Positive and Gram Negative bacteria
|
|
Define Narrow Spectrum Antibiotcs
|
Antibiotics are effective mainly against Gram Positive OR Gram Negative bacteria [Not completely one or the other]
|
|
Define Limited Spectrum Antibioitcs
|
Antibiotics are effective against a single organism or disease
|
|
Define Bactericidal Antibiotics
|
Antibiotics that can kill bacteria |
|
Define Bacteriostatic Antibiotcs
|
Antibiotics that stop the growth of bacteria
|
|
What are examples of some drugs that are '-static' at low doses and '-cidal' at higher doses?
|
Sulfonamides and Tetracyclines
|
|
What are the mechanisms of actions of Antimicrobials?
|
1) Inhibition of Cell Wall Synthesis 2) Inhibition of Protein Synthesis 3) Inhibition of Nucleic Acid (DNA/RNA) Synthesis 4) Inhibition of Synthesis of Essential Metabolites |
|
What are examples of antibiotics that inhibit cell wall synthesis?
|
Penicillin and Vancomycin
|
|
What are examples of antibiotics that inhibit protein synthesis?
|
Tetracycline, Chloramphenicol, Erythromycin and Streptomycin |
|
What are examples of antibiotics that inhibit Nucleic Acid (DNA/RNA) Synthesis?
|
Rifampin and Quinolones
|
|
What are examples of antibiotics that inhibit Syntheisis of Essential Metabolites?
|
Sulfa Drugs which inhibit syntheisis of Folic Acid
|
|
What is the MOA of Penicillins?
|
Inhibits cell wall synthesis using a Beta Lactam ring, killing the bacteria actively growing in the cell
|
|
What is the toxcity of Penicilins?
|
Non-Toxic but do produce allergic reactions sometimes
|
|
What are the characteristics of Penicillins?
|
Bactericidal, Broad Spectrum (+ve and -ve), (works with -ococus species)
|
|
What are examples of Penicillins?
|
Penicillin, Ampicillin and Cloxacillin
|
|
What are the four classifications of Penicillins?
|
1) Natural Penicillins 2) Pencillinase Resistant Penicillin 3) Extended Spectrum Penicillins (Aminopenicillins) 4) Antipseudomonal Penicillins |
|
What condition would you treat with Benzathaine Penicillin G?
|
Scarlet Fever |
|
What condition would you treat with Procaine Penicillin G?
|
Latent Syphillis
|
|
Penicillin G was the first drug of choice for:
|
1) Pneumocci(penumonia) 2)Streptocci 3) Meningeocacci 4) Spirochetes (treponema pallidum) 5)Non Beta lactamase producing staphylcocci 6)Clostridum(Actinomyces Species) 7)Non Beta Lactamase producing Gram(-ve) bacteria 8)Staph Aureus(NOW RESISTANT) |
|
What are examples of Penicillinase Resistant Penicillin?
|
Methicillin, Naficillin, Isoxazolyl Penicillins (oxacillin and cloxacillin)
|
|
What are examples of Extended Spectrum Penicillins?
|
Ampicillin and Amoxacillin
|
|
Are Penicillinase Resistant Penicillins sensitive to Beta Lactamases?
|
No, they are Beta Lactamase Resistant
|
|
Are Extended Spectrum Penicillins sensitive to Beta Lactamases?
|
Yes
|
|
What are examples of Antipseudomonal Penicillins?
|
Carbenicillin, Ticarcillin, Piperacillin and Mezlocillin
|
|
Are Antipsuedomonal Penicillins effective against Staph Aureus?
|
No, they are ineffective against Staph Aureus
|
|
Which penicillins are not effective orally?
|
Methicillin, Carbenicillin and others |
|
"Pen V, Amoxicillin and Amoxicillin/Clav are used orally only" True or False?
|
TRUE
|
|
"Cloxacillin is used orally only" True or False?
|
False, it is used both orally and parenteral |
|
"Oral Penicillin is unaffected by Foods" True or False?
|
False, It is impaired by food
|
|
How does probenecid prevent the excretion of Penicillin?
|
Probenecid uses the same steps of kidney excretions like penicillin and so competes with antibiotics for excretion and so they last longer in our bodies
|
|
"Penicillins are generally non-toxic" True or False?
|
TRUE
|
|
How does high dose of Peniciilins cause Seizures?
|
Accumulation of penicillin occurs with high doses and renal failure then the drug can penetrate into the CNS and this has an effect on the GABA receptors making them more active and this causes seizures |
|
How can Penicillins cause Hypokalemia?
|
Occurs with rapid intravenous doses of potassium penicillin G in patients with renal failure (also, excess sodium can also lead to Hypokalemia)
|
|
What are the mechanisms of antibiotic resistance?
|
1) Inactivation of Beta Lacatmases 2) Modifications of Target Penicillin Binding Protein (PBP) 3) Impaired Penetration of Drug to Target PBP 4) Efflux pump mechanisms to remove drug from the bacterial cell |
|
"Beta Lactamase Inhibitors have antibacterial action" True or False?
|
False, but remember that when adminstered alone with bacteria there is a slight decrease in bacterial growth.
|
|
What are the components of Augmentin?
|
Amoxicillin + Clavulinic Acid |
|
What are the components of Timentin ?
|
Ticarcillin + Clavulinic Acid
|
|
What is the MOA of Cephalosporins?
|
[Same as Penicillin] Beta Rings are used to break the cell walls of bacteria.
|
|
What is the toxcity of Cephalosporins?
|
[Same as Penicillin] Non-Toxic but can cause allergic reactions sometimes |
|
What are the characteristics of Cephalosporins?
|
Bactericidal, Broad Spectrum (Gram +ve and -ve) [better activity against gram +ve] |
|
"Cephalosporins are semisynthetic derivatives of fungus discovered in organisms isolated from a sewer in Sardinia" True or False?
|
True
|
|
What class of Cephalosporins is Cefazolin?
|
1st Generation
|
|
What class of Cephalosporins is Cefuroxime?
|
2nd Generation
|
|
What class of Cephalosporins is Ceftriaxone?
|
3rd Generation
|
|
What class of Cephalosporins is Cefixime?
|
3rd Generation
|
|
What class of Cephalosporins is Cefepime?
|
4th Generation
|
|
What are the properties of 1st Gen Cephalosporins?
|
Active against against Gram +ve and Gram -ve bacteria, and does not work on meningitis.
|
|
What are the properties of 2nd Gen Cephalosporins?
|
Less active against gram(+ve) and more active against gram(-ve). Not active against Enterocci and Psuedomonas aurgonisa. |
|
What are the properties of 3rd Gen Cephalosporins?
|
Even Less active against gram(+ve) than 2nd Gen. But with greater activity against gram(-ve) organisms. Good penetration into CNS. |
|
What are the properties of 4th Gen Cephalosporins?
|
Highest activity against gram(+ve) organisms, especially against penicillin resistant strain of streptocooci. |
|
What are the theraputic uses of 1st Gen Cephalosporins?
|
Oral: UTI infections, minor polymicrobial infections. Systemic: Surgical Prophylaxis
|
|
What are the theraputic uses of 2nd Gen Cephalosporins?
|
Lower respiratory tract infections, or Meningitis.
|
|
What are the theraputic uses of 3rd Gen Cephalosporins?
|
1st line drug for N.gonorrhoeae, used for sinusitis, meningitis and lower respiratory tract infections
|
|
What are the theraputic uses of 4th Gen Cephalosporins?
|
[Same as 3rd Gen] and Pseudomonas aeruginosa |
|
Which antibiotic is the only 1st Gen paraentral Cephalosporin?
|
Cefazolin
|
|
"All Cepalosporins are inactive against MRSA" True or False?
|
TRUE
|
|
Which generation of Cephalosporins are 1st Line for the treatment of N.gonrrhoeae
|
3rd Generation {4th as well?} |
|
What are the side effects of Cephalosporins?
|
1)Hypersensitivity 2)Neurotoxcity 3)Diarrhea 4)Nephritis 5)Cation toxcity 6)Hematologic toxcity [for 3rd gen] |
|
What is a "Super Infection"?
|
When the infection gets worse by being infected with a second strand while treating the first and the second is not as susceptible to the same antibiotic. |
|
What are the interactions of Cephalosporins?
|
1) Disulfiram effect with Alcohol 2)H2 Antagonists and Antacids decrease absorption by changing pH 3)Probenecid increases/prolongs effects of Cephalosporins [like penicillin] |
|
What is an example of a MonoBactam antibiotic?
|
Aztreonam
|
|
What are the properties of Azetronam?
|
Narrow Spectrum, active against gram(-ve) but NOT gram(+ve) or anerobic activity. |
|
What are the side effects of Azetronam?
|
Well tolerated, with little or no cross activity allergic reactions with Penicillins and Cephalosporins
|
|
What are the therapeutic uses of Azetronam?
|
Replacement for Aminoglycoside antibiotics.
|
|
What is an example of Carbapenems?
|
Imipenem, Meropenem
|
|
What are the properties of Carbapenems?
|
Most are broad spectrum and resistant to most beta lactamases |
|
What are the side effects of Carbapenems?
|
1)Nausea 2)Vomitting 3)Diarrhea 4)Skin Rashes 5)Comprimised renal function can give seizures |
|
Why is Cilastatin co-administered with Carbapenems ?
|
To inhibit peptidases which results in increased drug conc and to prevent cleavage and toxic metabolite formation |
|
What is the MOA of Vancomycin?
|
Inhibits cell wall synthesis in sensitive bacteria by binding with high affinity to D-Alanyl-D-Alanine
|
|
What are the characteristics of Vancomycin?
|
Gram(+ve) bacteria only, small glycoprotein water soluble and quite stable. |
|
What are the therapeutic uses of Vancomycin?
|
1) Gram (+ve) penicillin resistant disease and C.difficile 2)DOC for MRSA 3) Used with precaution in patients with true Beta Lactam allergy |
|
"Vancomycin is used routinely for Surgical Prophylaxis" True or False?
|
False, only used when the patient is allergic to Beta Lactams
|
|
"Vacomycin SHOULD NOT be used for systmeic/local prophylaxis of infections or colonization of indwelling central/peripheral IV catheters" True or False?
|
TRUE
|
|
"Vancomycin can be used for the empirical therapy of Febrile Neutropenia" True or False?
|
False, unless there is strong evidence of gram(+ve) infection |
|
"Vancomycin SHOULD NOT be used in tretment with response of a single blood culture positve for coagulase negative Staphylococci" True or False?
|
TRUE |
|
"Vacomycin SHOULD NOT be used for the primary treatment of antibiotic associated colitis" True or False?
|
True, only when resistant to Metronidazole
|
|
What is the one situation where Vancomycin is adminstered orally instead of IV?
|
Except for C.difficle
|
|
What are the side effects of Vancomycin?
|
1)Ototoxcity 2)Nephrotoxcity 3)Fever, Chills, Phlebitis at infusion site 4)Rash |
|
Why does Vancomycin need to be administered slowly via IV?
|
Because it causes histamine release hypotension [red man's syndrom] |
|
How does Vancomycin resistance develop?
|
1) Production of peptidoglycan precursor that Vancomycin cannot recognize. 2) Mutation in D-Alanyl D Alanine changes to D-Alanyl D Lactate or Serine, with low affinity to the loss of H-bonds |