APMLE Part 1 Exam- Pharm Test
|| With Complete Solutions (100%
Accurate)
CONCEPTIAL RESEARCH |
,APMLE Part 1 Exam- Pharm Test || With
Complete Solutions (100% Accurate)
Erythromycin - ANSWER - Macrolide antibiotic: *inhibitor of protein synthesis (50S)*;
activity includes gram− positive cocci and bacilli:
*Used for odd ball diseases*: Mycoplasma Infections, Legionnaires disease,
Chalamydial infections, Diptheria, Pertussis)
Tox: cholestatic jaundice, inhibits liver drug−metabolizing enzymes, interactions with
astemizole, theophylline, terfenadine, warfarin
Foscarnet - ANSWER - *Antiviral*: structural mimic of the anion *pyrophosphate*
that selectively inhibits the pyrophosphate binding site on *viral DNA polymerases* at
concentrations that do not affect human DNA polymerases.
*effective against CMV and HSV* (including TK− strains); PP analog.
Tox: electrolyte imbalance (chelates and increases Ca and Mg wasting),
nephrotoxicity
Ganciclovir - ANSWER - Antiviral: effective against CMV; *requires bioactivation via
thymidine kinase.* Ganciclovir triphosphate is a competitive *inhibitor of
deoxyguanosine triphosphate (dGTP) incorporation into DNA* and preferentially
inhibits viral DNA polymerases more than cellular DNA polymerases.
Tox: myelosuppression, nephrotoxicity
Gentamicin
Tobramycin
Amikacin
neomycin
netilmicin
Streptomycin - ANSWER - Aminoglycoside prototype: *bactericidal inhibitor of
protein synthesis (30S)*; Active against many aerobic gram−negative bacteria.
Anaerobes are resistant, do not have O2 pumps, to get drug into bug.
*Penicillin is used to open pores in cell wall which promote entry of aminoglycosides
into to cell to bind to ribosomes. (GTQ)*
Narrow Therapeutic of index, peak and trough. = *Tox: Ototoxicity (cochlear) out hair
cell destruction in the organ of corti, Vestibular toxicity (balance)*: Think ringing/
tennitus, deafness, vertigo, high fq hearing loss.
Imipenem
Meropenem - ANSWER - Antibiotic: carbapenem *(all have "penem" in name)* - all
given IV. Betalactam active against many aerobic and anaerobic bacteria including
penicillinase−producing organisms; a bactericidal inhibitor of cell wall synthesis.
, *Used with cilastatin* (which inhibits metabolism by renal dehydropeptidases).
Otherwise toxic metabolite in kidney.
Tox: allergy (partial cross−reactivity with penicillins), seizures (overdose)
*Meropenum* more stable, less toxic, no need to use w/ cilastatin.
Indi*navir* - ANSWER - Antiviral; *HIV protease inhibitor* used as component of
combination regimens in AIDS.
Tox: anemia, nephrolithiasis, inhibits P−450 drug metabolism reactions. Other
protease inhibitors: ritonavir, nelfinavir, saquinavir
Interferon−α - ANSWER - Important cytokine for the treatment of hepatitis B and C
infection.
Isoniazid - ANSWER - Antimycobacterial: primary drug in combination regimens (6-
12mo) for tuberculosis (TB); used as sole agent in prophylaxis - *Inhibits synthesis of
mycolic acids*
Metabolic clearance via N−acetyltransferases (*genetic variability -
pharmacogenomics* between slow and fast acetylators - *slow accumulates drugs,
peripheral neuropathy)*
Tox: hepatotoxicity (age−dependent), *peripheral neuropathy (reversed by
pyridoxine aka B6)*, hemolysis (in G6PD deficiency)
Ketoconazole - ANSWER - *Antifungal azole* prototype: active systemically; inhibits
the synthesis of ergosterol in fungus (part of fungal cell membrane).
Used for C.Albicans, dermatophytes and for non−life−threatening systemic mycoses.
Tox: hepatic dysfunction, inhibits steroid synthesis and P450−dependent drug
metabolism
Metronidazole - ANSWER - Antiprotozoal antibiotic: drug of choice in extraluminal
amebiasis and trichomoniasis; active against bacterial anaerobes including B fragilis
and in antibiotic−induced colitis due to C difficile. *It is the drug of choice for first
episodes of mild-to-moderate Clostridium difficile infection.*
Tox: peripheral neuropathy, gastrointestinal distress, ethanol intolerance, mutagenic
potential
Nafcillin - ANSWER - Penicillinase−resistant penicillin prototype: used for suspected
or known staphylococcal infections; not active against methicillin−resistant
staphylococci.
Tox: penicillin allergy