Chapter 17 Exam Flashcards
Culture and sensitivity
24-48 hours
Empiric
best guess based on history
Resistance-
no longer effective
why would something be resistant?
- Frequent use
* Incomplete treatment
Factors in the selection of anti-infective drugs (6)…
- Infection site
- Status of hepatic and/or renal function
- Patient age
- Pregnancy or lactation
- Likelihood of organisms developing resistance
- Known allergy to the anti-infective drug
Allergic hypersensitivity-
- Over-response of the body to a specific substance
* Anaphylaxis
Superinfection-
• Manifested as a new infection due to absence of normal flora in the intestines or mucous membranes
symptoms of superinfection
diarrhea, vaginitis, stomatitis, glossitis
when are Aminoglycosides used?
• Only when less toxic drugs are ineffective or contraindicated
how are aminoglycosides usually administered?
• Usually administered IM or IV
examples of aminoglycosides…
• Ex: gentamycin, amikacin, tobramycin
Cephalosporins-
• Semisynthetic beta-lactam antibiotic derivatives produced by a fungus
Cephalosporins (Related to penicillin )
- Some patients allergic to penicillin are also allergic to cephalosporin
- Considered broad-spectrum
how are cephalosporins classified?
• Classified as first, second, third, or fourth, or fifth generation
Macrolides-
• Treats many infections of the respiratory tract, skin conditions, or for some STIs when patients are allergic to penicillin
what are considered among the least toxic antibiotics?
Macrolides
when are macrolides preferred?
for treating susceptible organisms under conditions in which more toxic antibiotics might be dangerous
what are ex of susceptible organisms?
patients with renal disease, pregnant woman, or infants
examples of macrolides
erythromycin (E.E.S.)
clarithromycin (Biaxin)
azithromycin (Zithromax)
Penicillins def…
• Beta-lactam antibiotics produced from certain species of a fungus
what do penicillins treat?
• Treats many streptococcal and some staphylococcal and meningococcal infections
what is penicillin the drug of choice for?
treatment of syphilis
what are penicillins used prophylactically for?
prevent recurrences of rheumatic fever
Amoxicillin before dental procedures does what?
prevent infective enodcarditis
what are ex of penicillins?
penicillin G, penicillin VK, amoxicillin, ampicillin
Carbapenems def…
Belong to the beta-lactam class of antibiotics and have a very broad spectrum of activity against gram-negative and gram-positive organisms
primary treatments of carbapenems
pneumonia, febrile neutropenia, intra-abdominal infections, diabetic foot infections, and significant polymicrobial infections
ex of carbapenems
meropenem (Merrem)
Quinolones
• For adult treatment of some infections of the urinary tract, sinuses, lower respiratory tract, GI tract, skin, bones, and joints, and in treating gonorrhea
Some organisms are showing ___________ towards quinolones
increased resistance
quinolones should be reserved for what?
Should reserve these agents for infections requiring fluoroquinolones or when patients are allergic to other antibiotics
ex of quionolones
ciprofloxacin (Cipro)
levofloxacin (Levaquin)
Tetracyclines-
• Treats infections caused by rickettsia, chlamydia, or some uncommon bacteria, some STIs, and some severe acne cases
tetracyclines should only be used when…
other antibiotics are ineffective or contraindicated
examples of tetracyclines
tetracycline, doxycycline (Vibramycine), tigecycline (Tygacil)
antifungal agents
treat specific susceptible fungal disease
amphotericin B (Abelcet)
Administered IV for the treatment of severe systemic and potentially fatal infections caused by susceptible fungi including Candida
• Can cause serious side effects so close medical supervision needed
• fluconazole (Diflucan)
• Works against many fungal pathogens, including most Candida, without the serious toxicity of amphotericin B
• micafungin (Mycamine)
- Provides new treatment options against Candida and Aspergillus species
- Prophylaxis for stem cell transplantation
how is micafungin give?
given through IV
• nystatin
- Structurally related to Amphotericin B
- Orally treats oral cavity candidiasis
- Also used as a fungicide in the topical treatment of skin and mucous membranes
• Tuberculosis (TB)
• Caused by a bacterium called Mycobacterium tuberculosis, which primarily attacks the lungs
• Antituberculosis agents are administered for two purposes
- To treat latent or asymptomatic infection (no evidence of clinical disease; but + TB test)
- For treatment of active clinical tuberculosis and to prevent relapse – multi-drug regimen
how to treat asymptomatic infection (tuberculosis)…
Daily administration of isoniazid (INH) for 6-12 months
Examples of medications used for TB
- ethambutol (Myambutol)
- isoniazid (INH)
- pyrazinamide (PZA)
- rifampin (Rifadin)
- streptomycin
What is the drug of choice for MRSA?
• vancomycin (Vancocin)
SMX stands for?-
sulfamethoxazole
TMP stands for?-
trimethoprim
What is Bactrim?
sulfamethoxazole (SMX) and trimethoprim (TMP) combined
what is bactrim used for?
for the treatment of UTIs
What is nitrofurantoin used for?-
First-line urinary anti-infectives for empiric treatment of uncomplicated lower UTI
oseltamivir (Tamiflu) belongs to what class of antivirals?-
- Neuraminidase inhibitors
HAART
highly active antiretroviral therapy
ARV
antiretroviral agents
What is the usual therapeutic regimen for these agents? (HIV/AIDS)
• The primary approach to therapy is disruption of the virus at different stages in its reproduction
• Antiretroviral protease inhibitors (PIs)
• Block the activity of the HIV enzyme essential for viral replication late in the virus life cycle
• Nucleoside reverse transcriptase inhibitors (NRTIs)
• Inhibit an enzyme responsible for viral replication early in the virus life cycle
example of NRTI
• Combivir (combination of lamivudine & zidovudine) is a NRTI used in combination with other ARVs
• Non-nucleoside reverse transcriptase inhibitors (NNRTIs)
• Inhibit an enzyme responsible for viral replication early in the viral life cycle
• Fusion inhibitors (FIs)
• Block entry of HIV into cells, which may keep the virus from reproducing
• CCR5 antagonists
• Block a co-receptor required for HIV entry into human cells
• raltegravir (Isentress):
first ARV designed to slow the advancement of HIV infection by blocking the enzyme needed for viral replication
