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NURS 615 Exam II with Detailed Answers
1. What blood values should be monitored with carbamazepine?: Plasma car- bamazepine levels
should be monitored on a regular basis. The therapeutic range is 4 to 12 mcg/L. Higher levels can lead to toxic symptoms consisting of initial adverse effects and also hypertension, tachycardia, ECG changes, stupor, agitation, nystagmus, urinary retention, respiratory depression, seizures, and coma. Children and elderly patient may develop toxicity levels below
CBC every 3 to 4 months Affects RBC, WBC, Platelets Agranulocytosis, Anemia
2. What is the pharmacodynamics of carbamazepine?: Carbamazepine is me- tabolized in the liver
and has the unique ability to induce its own metabolism (autoinduction). Due to autoinduction, initial concentrations within therapeutic range may later fall despite good compliance. It also induces the metabolism of many CYP450 enzymes and other substances. Slowly but well absorbed half life of about 30 hours, shortens to 15 hours when given repeatedly The exact mechanism of action of carbamazepine is not known, but they are thought to affect the sodium channels, slowing influx of sodium in the cortical neurons and slowing the spread of abnormal activity. Carbamazepine exerts its effect by depressing transmission in the nucleus ventralis anterior of the thalamus. This area is associated with the spread of seizure discharge.
- Absorption and Distribution Carbamazepine is absorbed through the stomach, the suspension being absorbed more quickly
than the tablet form. Absorption from the immediate-release tablets is slow and erratic because of its slow water solubility. The drug is highly lipophilic, resulting in high body tissue binding.
- Metabolism and Excretion Excretion is through feces and urine. Average blood levels of carbamazepine occur approximately 6 hours after adminis- tration. Half- life can be as long as 65 hours with initial dosing, but is typically 12 to 17 hours as administration continues. It is noteworthy that the half-life after a single dose is much longer than the half-life after long-term use. Steady state is attained in 2 to 4 days.
3. What should families be taught regarding the monitoring of seizure activi- ty?: Patients should be
monitored for seizure activity, severity, and duration. Patient should carry medical identification for the seizure disorder. Patient should report any mood changes or suicidal thoughts. Prevention of seizures. Do not abruptly end medication increases risk of seizures
4. What electrolyte imbalance is noted with the administration of topiramate?-
: Patients taking topiramate may have decreased concentrations of bicarbonate due to inhibition of carbonic anhydrase and increased renal bicarbonate loss, leading to hyperchloremic metabolic acidosis. Severe metabolic acidosis has been reported in infants receiving a topiramate dose of 5mg/kg/day. Serum bicarbonate levels should be monitored at baseline and periodically throughout therapy.
5. What is the pregnancy category for valproate?: Pregnancy Category X.
6. What instructions will you provide to a woman who wants to get pregnant and has a seizure
disorder controlled with valproate?: Switch to another anti- seizure medication such as Keppra Use of these drugs during the first trimester of pregnancy is associated with neural tube defects
nightmares have been noted following abrupt discontinuance of the drug or after large dose decreases.
- Lower seizure thresholds in those with seizure disorder or those taking medications that also decrease seizure threshold.
- Therapeutic and toxic level index is LOW. Great care needs to be taken when prescribing for a person who is depressed and has suicidal ideas.
- APRNs need to be alert for an energizing effect that precedes depressive symptom remission because this may contribute to sufficient activation to follow through with a suicidal plan. Patients need to be monitored on a weekly basis, especially regarding suicidal thoughts and behaviors, and medication should be dispensed in only small amounts until suicidal risk decreases.
- Used in extreme caution in the elderly due to their anticholinergic and norepineph- rine effects they contribute to confusion, orthostatic hypotension, and falls.
8. Phenelzine (Nardil) is an MAO inhibitor. What are the cautions and con- traindications? How is it
used to treat recalcitrant depression?: •Contraindica- tions Liver or kidney disease Hypersensitivity Congestive heart failure or arteriosclerotic disease Age over 60 years Pregnancy category C; excreted in breastmilk safety not established Not approved for use with children Postural hypotension and suppression of myocardial pain may occur.
- MAOIs exert their effect by irreversibly inactivating the enzymes that metabolize norepinephrine, serotonin, and dopamine, thereby increasing the bioavailability of these neurotransmitters. FUll 2 weeks to clear from system should wait that long to start a different therapy
9. What are the symptoms of hypertensive crisis?: •MAOIs inhibit the metabo- lism of
norepinephrine and can cause hypertensive crisis. Foods high in tyramine should be restricted because of this risk as well as they are the precursor to dopamine, norepinephrine, and epinephrine.
- Treatment of hypertensive crisis needs to be managed immediately, and the patient should remain standing until it is. Usual treatment is phentolamine (Regitine) 5mg IV and then 0.25mg to 0.5mg IM every 4 to 6 hours.
- Hypertensive crisis symptoms include: Headache Heart palpitations Stiff/sore neck Chest tightness Tachycardia Sweating Dilated pupils
10. How long does it take for selective serotonin reuptake inhibitors to pro- duce an effect in patients
pregnancy category A antibiotics and are safest prescribe in pregnancy.
16. Which antibiotics inhibit bacterial cell wall synthesis?: Beta-lactams; peni- cillins,
cephalosporins, carbapenems, and monobactams, have similar mechanisms. They are most effective against rapidly growing organisms forming cell walls.
17. Why is clavulanate added to amoxicillin?: Because of increasing beta-lac- tamase production
among gram-negative pathogens and anaerobes, amoxicillin and ampicillin are often combined with beta-lactamase inhibitors, clavulanic acid, and sulbactam, respectively, for enhanced gram-negative and anaerobic activity. Beta-lactamase inhibitors prevent the destruction of beta-lactam antibiotics by serv- ing as a competitive inhibitor of beta-lactamase.
18. What antibiotics are appropriate to prescribe to children?: Amoxicilln is the top antibiotic
prescribed to children. A penicillin is usually the drug of choice for a susceptible organism because of limited toxicities.
19. According to the American College of Cardiology and the American Heart Association, what are
the guidelines related to prophylactic antibiotics prior to a dental appointment?: A joint task force from the American College of Cardiology and the American Heart Association recently published a document that currently recommends therapy only for those with prosthetic heart valves, previous infective endocarditis, certain patients with congenital heart disease, and cardiac transplant patients with valve regurgitation who are undergoing dental procedures that involve manipulation of either gingival tissue or the periapical region of the teeth. Patients with CHD who require prophylaxis include CHD repaired prophylaxis include those with unrepaired cyanotic CHD, completely repaired first 6 months after repair, and repaired CHD with residual effects at the site of the prosthetic patch or device.
20. What patient teaching will you provide to a patient who is experiencing
non- infectious diarrhea related to antibiotic administration?: If severe diarrhea occurs, the patient
should contact the prescriber before initiating any treatment. For mild diarrhea, they can also use adsorbent antidiarrheal agents containing attapulgite (e.g., Donnagel) but should avoid antiperistaltic agents that promote the retention of toxins.
21. A patient is taking a fluoroquinolone; what are the most serious adverse effects?: All
fluoroquinolones have a Black-Box Warning regarding the risk of ten- don rupture and tendonitis. The risk is increased in older patients; in patients taking coritocosteroids; and patients with heart, kidney, or lung transplant. An additional Black Box Warning has been issued for all fluoroquinolones to avoid this class in patients with myasthenia gravis.
22. What population should not be administered tetracyclines and why?: - There are a number of
patients for whom tetracyclines should be prescribed cautiously; such patients include those with renal impairment, those with hepatic impairment, pregnant women, lactating women, and children under the age of 8 years old. Doxycycline is Pregnancy category D. Others are Pregnancy category X and should not be used during pregnancy. They readily cross the placenta in concentrations up to 60% of maternal plasma. Tetracyclines are found in fetal tissue and can produce retardation of skeletal development in the fetus and staining of deciduous teeth. Children younger than 8 years generally should not use any tetracycline. These drugs form a stable calcium complex in any bone forming tissue, decreasing bone growth. They also may cause permanent yellow/gray/brown discoloration of decidu- ous and permanent teeth. Enamel hypoplasia has also been reported. Doxycycline
100mg/meal
26. What is the course of treatment with doxycycline for the treatment of Lyme Disease?:
Doxycycline, 100mg twice daily is the first line drug of choice for early treatment of Lyme disease, a tick borne infection caused by B. burgdorferi.
27. What are the main side effects of doxycycline?: Can cause phototoxicity, so sunlight and
tanning lights should be avoided. Wear sunscreen, hats, and protective clothing if necessary to be in the sun for more than a few minutes. Differentiate between oral and parenteral vancomycin
28. Differentiate between oral and parenteral vancomycin.: Absorption of van- comycin form the GI
tract is poor, although clinically significant serum concentrations have occurred. When administered intravenously, onset of action is rapid, with peak concentrations in 1 hour and a duration of effect of approximately 12 hours, depending on renal clearance. It is 52% to 56% protein bound and has less than 1% bioavailability by the oral route. Its half-life is 4 to 6 hours in adults and 2 to 3 hours in children. Distribution is wide, with 20% to 30% penetration of the CSF. The drug crosses the placenta.
29. What is the mechanism of action of azithromycin?: Binds to the P site of the 50S ribosome
subunit of susceptible organisms and may inhibit RNA-dependent synthesis by stimulating the disassociation of peptidyl-tRNA from ribosomes. These drugs are typically bacteriostatic but may be bactericidal depending on drug con- centrations and the bacterial species tested. Macrolides are weak bases, and their activity increases in alkaline media.
30. Which antibiotics block bacterial protein production?: Tetracyclines inhibit protein synthesis
by reversibly binding to the 30S subunit of the bacterial ribosome and preventing the addition of amino acids to growing peptides.
31. What vitamin will decrease peripheral neuropathy?: Vitamin B12 or folate vitamin
supplementation will decrease peripheral neuropathy.
32. What lab values should be assessed when administering valacyclovir?: - BUN and serum
creatinine may be assessed prior to therapy in those with risk factors for renal impairment and periodically during prolonged therapy to detect changes in renal function.
33. When should oseltamivir phosphate be prescribed?: Tamiflu is used for the prophylaxtic
treatment of influenza A and B.
34. For what is rifampin prescribed?: Tuberculosis, particularly in patients with HIV
Rifampin is also used to treat several nonmycobacterial infections. It is used as prophylaxis for close contacts of people with meningococcal infections caused by N. meningitis. Prophylaxis for H. influenzae type b Off label treatment of leprosy
35. What are the adverse effects of isoniazid (INH)?: Elevated AST/ALT levels are observed in 10%
to 20% of patients taking isoniazid. A small group of patients may progress to progress to hepatic failure or necrosis. The symptoms are those usually associated with the function of development of hepatitis, including abnormal liver function studies, jaundice, and fatigue.
36. When is prophylactic oseltamivir recommended?: The only strongly rec- ommended for
prophylaxis, particularly when an unvaccinated high risk patient is exposed to influenza.
37. When prescribing ketoconazole, how should it be administered?: Maximal daily dosage is 1g.
Therapy should be continued 1-2 weeks in candidiasis (3-5 days in vaginal candidi- asis).
Tissue nematodes--mebendazole, albendazole, or ivermectin
41. What antifungal medications can be used topically to treat fungal infec- tions?: •Nystatin
- Clotrimazole
- Ketoconazole
- Econazole and Oxiconazole
- Terbinafine and Naftifine
- Tolnaftate
- Butenafine
- Ciclopirox
42. What are the main side effects of ethambutol?: GI disturbances Optic neuritis,
which appears to be dose related. S/S include--decreased visual acuity, red-green color blindness, diminished visual fields, and sometimes loss of vision Precipitation of gouty arthritis (elevated uric acid levels) Transient impairment of liver function Infrequent peripheral neuropathy
43. What medication is used to treat scabies?: Ivermectin may be prescribed off-label to selected
patients with scabies. It is effective in treating scabies in patients who are immunocompromised. The dose is 200 mcg/kg given in a single dose. Because Ivermectin is not ovicidal, it should be repeated in 1 to 2 weeks.
44. What are the side effects of rifampin?: Hepatotoxicity leading to hepatitis occurs with
rifampin. A harmless orange-red discoloration of body fluids including tears, saliva, urine, sweat, CSF, and feces also occurs. Hematuria should not be confused with this discoloration because of hematuria may be an indication of a hypersensitivity reaction.
