NAPLEX Practice Exam Questions with Answers North American Pharmacist Licensure Examination Certification

Primidone is an anticonvulsant drug that is structurally related to phenobarbital. Primidone is metabolized to

phenobarbital and therefore shares its anticonvulsant and sedative properties. Primidone may be more effective than therapy with phenobarbital alone because primidone and both of its metabolites, phenobarbital and phenylethylmalonamide (PEMA), possess anticonvulsant activity.

Gestational diabetes is typically asymptomatic but identified via a 1-hour 50g oral glucose challenge administered at 24–28 weeks of gestation. A venous plasma glucose blood level of > 140 mg/dL is suggestive, and must be confirmed with a 3-hour 100g oral glucose tolerance test. After administration of the 100g glucose challenge, at least two of the following are required for diagnosis: (1) fasting glucose > 95 mg/dL, (2) one-hour glucose >180 mg/dL, (3) two hour glucose >155 mg/dL, and (4) three hour glucose > 140 mg/dL. Choice A –

To diagnose gestational diabetes, a positive 1-hour 50g oral glucose challenge must be followed up by a three-hour 100g oral glucose challenge. The diagnosis is only confirmed after both challenges are completed and the thresholds are met. Choice C – Following the diagnosis of gestational diabetes, the first step is strict glycemic control (fasting glucose).

Thiazolidinediones may cause fluid retention through proposed mechanism of increasing reabsorption in the collecting duct of the kidney and increasing vascular permeability in adipose tissue. Bile acid sequestrants work in the intestine to bind bile acids which doesn’t affect fluid retention. GLP-1 receptor agonists work to activate these receptors to secrete insulin from beta pancreatic cells/decrease glucagon secretion/ increase satiety and doesn’t affect fluid retention. SGLT2 inhibitors actually cause increase of fluid elimination through the kidneys. Alpha-glucosidase inhibitors work in the gut to decrease carb absorption/digestion and have no affect on fluid retention.

40mEq × 1equiv/1000mEq × 74.5g/1equiv = 2.98 gm of KCl in 100ml. Calculate: mOsm/L. 2.98g/100ml × 1mol/74.5g × 2Osm/1mol × 1000mOsm/ Osm × 1000ml/1L = 800mOsm/L

The dihydropyridine drug – nifedipine – is the active ingredient found in the medicine Adalat. Nifedipine is used to treat angina, Reynaud’s phenomenon and hypertension. It is also used as a tocolytic agent in premature labor.

SGLT2 inhibitors Sulfonylureas work in beta cells in the pancreas that are still functioning to enhance insulin secretion. Alpha-Glucosidase Inhibitors stop ?-glucosidase enzymes in the small intestine and delay digestion and absorption of starch and disaccharides which lowers the levels of glucose after meals. DPP4 blocks the degradation ofGLP-1, GIP, and a variety of other peptides, including brain natriuretic peptide. Glucagon-like peptide-1 receptor agonists work in various organs of the body. Glucagon-like peptide-1 receptor agonists enhance glucose homeostasis through: (i) stimulation of insulin secretion; (ii) inhibition of glucagon secretion;

(iii) direct and indirect suppression of endogenous glucose production; (iv) suppression of appetite; (v) enhanced insulin sensitivity secondary to weight loss; (vi) delayed gastric emptying, resulting in decreased postprandial hyperglycaemia. Thiazolidinediones are the only true insulin-sensitising agents, exerting their effects in skeletal and cardiac muscle, liver, and adipose tissue. It ameliorates insulin resistance, decreases visceral fat. Biguanides work in liver, muscle, adipose tissue via activation of AMP-activated protein kinase (AMPK) reduce hepatic glucose production. SGLT2 inhibitors work in the kidneys to inhibit sodium-glucose transport proteins to reabsorb glucose into the blood from muscle cells; overall this helps to improve insulin release from the beta cells of the pancreas.

Risk factors for myopathy are hypothyroidism, reduced renal or hepatic function, rheumatologic disorders such as polymyalgia rheumatica, steroid myopathy, vitamin D deficiency, or primary muscle diseases.

Metoclopramide may cause tardive dyskinesia when given at a higher dose and for a long duration of time of more than 3 months. Tardive dyskinesia is also listed as a Boxed Warning for metoclopramide. Tardive dyskinesia is a serious movement disorder that is irreversible. The risk increases with duration of treatment

and the total cumulative dose. If signs or symptoms of tardive dyskinesia develop, then metoclopramide should be discontinued. There is currently no known treatment for it, but symptoms can lessen or resolve after metoclopramide is stopped. Treatment should not be more than 12 weeks unless the benefits outweigh the risks of developing tardive dyskinesia.

A CD4 count of 180 cells per cubic meter is considered very low – typically an indicator that the patient has an immunocompromised state, such as AIDS. CD4 counts are a measure of healthy T-cell levels. The lower the count, the more susceptible the patient is to opportunistic infections. A normal range is between 500 and 1,500 cells.

In the management of acute ischemic stroke, alteplase should be administered within 3 hours of symptom onset.

DPP4 Inhibitors, D Glucagon-like peptide-1 receptor agonists Sulfonylureas work in beta cells in the pancreas that are still functioning to enhance insulin secretion. Alpha-Glucosidase Inhibitors stop ?-glucosidase enzymes in the small intestine and delay digestion and absorption of starch and disaccharides which lowers the levels of glucose after meals. DPP4 blocks the degradation ofGLP-1, GIP, and a variety of other peptides, including brain natriuretic peptide. Glucagon-like peptide-1 receptor agonists work in various organs of the body. Glucagon-like peptide-1 receptor agonists enhance glucose homeostasis through: (i) stimulation of insulin secretion; (ii) inhibition of glucagon secretion; (iii) direct and indirect suppression of endogenous glucose production; (iv) suppression of appetite; (v) enhanced insulin sensitivity secondary to weight loss; (vi) delayed gastric emptying, resulting in decreased postprandial hyperglycaemia. Thiazolidinediones are the only true insulin-sensitising agents, exerting their effects in skeletal and cardiac muscle, liver, and adipose tissue. It ameliorates insulin resistance, decreases visceral fat. Biguanides work in liver, muscle, adipose tissue via activation of AMP-activated protein kinase (AMPK) reduce hepatic glucose production. SGLT2 inhibitors work in the kidneys to inhibit sodium-glucose transport proteins to reabsorb glucose into the blood from muscle cells; overall this helps to improve insulin release from the beta cells of the pancreas.

Since the bioavailability of levothyroxine is roughly 50% (given in the QUESTION NO:). To convert the home dose to intravenous, it would be 50% of the oral dose. So 50% of oral 75 mcg would be 37.5 mcg intravenously.

Influenza vaccine is recommended annually, thus, WM should not skip it this year, and B is incorrect. Also, per the CDC, seasonal influenza outbreaks can occur as early as October, however, most activity peaks in January or later. Thus, it is not too late for WM to receive his vaccine in December, thus A is incorrect. Lastly, antiviral medications such as Tamiflu are an important adjunct to vaccinations. They are recommended as early as possible for any patient with confirmed or suspected influenza who, is 1) Hospitalized, 2) has severe, complicated, or progressive illness or 3) is at higher risk for influenza complications. Thus, WM is not a candidate with the given information and C is incorrect. Starting Tamiflu or Amantadine is not recommended for prevention. It has indication for treatment and prophylaxis.

Dichotomous data is considered categorical data that only has two categories, or two answer choices. All 3 answer choices have only 2 categories: sex has male or female, pain is yes or no, and alive or dead is only two options also.

The delayed-release action of divalproex allows for less frequent dosing than valproic acid in some patients. Divalproex sodium contains sodium valproate and valproic acid in a 1:1 molar stable co-ordination compound. Valproic acid, sodium valproate, and divalproex share the same pharmacology; however, there are pharmacokinetic differences among products.

Common GI side effects of Valproic Acid and Divalproex Sodium are Weight gain, Nausea, Vomiting, Diarrhea, abdominal pain, dyspepsia. Divalproex sodium or valproic acid affects reproductive endocrine function in women. Menstrual irregularities defined as amenorrhea, oligomenorrhea, and prolonged cycles were common. Gynecomastia is not a side effect of Divalproex Sodium. For list of drugs that causes gynecomastia refer the reference. Gingival hyperplasia is a well-known side effect of phenytoin.

Ceftaroline covers MRSA, but it does not cover pseudomonas. Ertapenem does not cover pseudomonas. Cefazolin does not cover MRSA nor Pseudomonas. Cefepime has pseudomonas coverage. Vancomycin does not cover gram negative bacteria.

Primary treatment for stenotrophomonas maltophilia is SMX-TMP. Meropenem, ciprofloxacin, Ampicillin and vancomycin have no coverage.

Dexamethasone is associated with psychiatric disturbances. Corticosteroids may exacerbate pre-existing psychiatric conditions.

Omeprazole is CYP2C19 inhibitor which can prolong the elimination of warfarin, particularly R-warfarin. R- warfarin is partially metabolized by CYP2C19. The combined use of omeprazole and warfarin has been associated with reports of increased INR and prothrombin time (PT).

The only bile acid sequestrant, colesevelam (Welchol), has been shown to increase triglycerides through mechanism of: activation of phosphatidic acid phosphatase with promotes triglyceride synthesis. GLP-1 agonists work on GLP 1 receptors to increase insulin secretion, decrease glucagon secretion, and increase satiety. Thiazolidinediones activate nuclear transcription factor PPAR gamma to increase insulin sensitivity. SGLT2 inhibitors inhibit glucose reabsorption in the kidney. Alpha-glucosidase inhibitors slow down digestion and absorptions of carbs in the gut.

This patient shows symptoms of acute sinusitis. The most common etiology of which is viruses. Indications that an infection is viral as opposed to bacterial included a shorter infection tie (less than 10 days) and no purulent discharge (hers is watery). She does not show any evidence of a complication developing and even notes that her symptoms are improving. If her symptoms were attributed to a bacterium, then the most common cause of acute sinusitis is Streptococcus pneumoniae followed by Haemophilus influenza, then Moraxella catarrhalis. Anaerobic species such as Bacteroides fragilis and Staphylococcus aureus are more commonly found in patients with chronic sinusitis (sinusitis lasting longer than 12 weeks). This is important to realize before indiscriminately providing antibiotics for these patients.

Propylthiouracil (PTU) is recommended for treatment of hyperthyroidism in women who are in their first trimester of pregnancy by the American Thyroid Association (ATA). Methimazole has been associated with congenital malformations including aplasia cutis in rare cases and thus it is not recommended in the first trimester. The ATA recommends switching to methimazole once in the second trimester as there is a risk of liver injury associated with the use of PTU.

Lisinopril may increase LN’s potassium. One of the warnings/precautions of lisinopril is hyperkalemia. ACE inhibitors block the formation of circulating angiotensin II, which can lead to a decrease in aldosterone secretion that can result in an increase in potassium. Risk factors for hyperkalemia while taking lisinopril include renal impairment, diabetes, and concomitant use of potassium-sparing diuretics, potassium

supplements and/or potassium containing salts. Potassium should be monitored closely when taking any of the other agents listed. Hyperkalemia is not listed in the warnings/precautions section for the other medications.

Pt’s weight in Kg 76.4. 76.4 × [5 mcg/kg/min] = 381.18 mcg/min Concentration of the bag [400 mg/250 mL] = 1.6 mg/ml or 1600mcg 381.18 mcg × [1 mL/1600 mcg] = 0.2382 mL/ml 60 in × [0.0.2382 mL/min] = 14.29 mL in one hour

0.05 (1000 mL) = 50 g 1000 mL × (1 hour/125 mL) = 8 hours 50 × 3 = 150 g

Dexamethasone can increase LN’s blood glucose. All glucocorticosteroids are known to increase blood glucose. Blood glucose would need to be monitored while LN is being treated with dexamethasone.

B: A variety of drugs have been found to be of some value in the prevention and treatment of vomiting, especially cancer chemotherapy-induced vomiting. With the exception of thioridazine, most of the neuroleptic drugs have antiemetic effects that are mediated by blocking D2 dopaminergic receptors of the chemoreceptor trigger zone of the medulla. Phenothiazines, such as prochlorperazine, were the first drugs shown to be effective antiemetic agents and act by blocking dopamine receptors. They are effective against low to moderately emetogenic chemotherapeutic agents (for example, fluorouracil and doxorubicin). Although increasing the dose improves antiemetic activity, side effects, including hypotension and restlessness, are dose limiting. Other adverse reactions include extrapyramidal symptom and sedation. A: Serotonin 5-HT3 antagonist is incorrect. The specific antagonists of the 5-HT3 receptor, ondansetron and granisetron, selectively block 5-HT3 receptors in the periphery and in the brain (chemoreceptor trigger zone). C: Cannabinoids related is incorrect. Cannabinoids are marijuana derivatives including dronabinol and nabilone and are effective against moderately emetogenic chemotherapy. However, they are seldom first-line antiemetics because of serious side effects. D: Blockage of prostaglandins is incorrect. Dexamethasone and methylprednisolone used alone are effective against mildly to moderately emetogenic chemotherapy. Their antiemetic mechanism is not known, but it may involve blockade of prostaglandins. E: H2 receptor antagonist is incorrect. Antagonists of histamine H2 receptor block the action of histamine at all H2 receptors; their chief clinical use is as inhibitors of gastric acid secretion.

Benign prostatic hyperplasia (BPH) is an example of postrenal acute kidney injury (AKI). Postrenal AKI, as the name suggests, involves an effect ‘post’ or ‘beyond’ the kidney, to problems that emerge downstream from the kidney. BPH is one such example of that. Other examples include kidney stones, bladder stones and bladder cancer.

Incidence rate = New reported cases / summed person-years of observation (avg population during time interval). Prevalence = Cases in a population in a given time period / total population at that time Mortality rate

= deaths during specified time interval / population size at risk for death.

Drugs mainly interact with the receptors by means of chemical forces or bonds. There are three major types of drug receptor bonds: - Covalent - Electrostatic - Hydrophobic Covalent bonds are very strong bonds and in most of the cases they are irreversible under biologic conditions. For example, the covalent bond between the acetyl group of aspirin and cyclo-oxygenase enzyme (target enzyme present on the platelets) does not breaks easily. The platelet aggregation effect of aspirin lasts long after free acetyl-salicylic acid has disappeared from the blood (about 15 minutes) and it is reversed only by the synthesis of new cyclo-oxygenase enzyme in new platelets which takes a long time. Hence the effect of aspirin is seen after the drug is stopped. Among the drug receptor interactions, electrostatic bond is much more commonly found than covalent bond. The electrostatic bonds vary from relatively strong linkages between permanently charged ionic molecules to weaker hydrogen bonds and very weak induced dipole interactions such as van der Waals force. The electrostatic bonds are weaker than covalent bonds. Hydrophobic bonds are usually very weak bonds and probably important in the interactions of highly lipid soluble drugs with the lipids of cell membranes and perhaps in the interactions of the drugs with the internal walls of receptor “pockets”.

[1 mg/ 1 min] × 60min= 60mg/hr. 60 mg/hr × [1 mL/ 1.8 mg] = 33.33 mL/hr 0.5 mg/min × [60 min/ 1 hr] = 30 mg/hr 30 mg/hr × [1 mL/1.8 mg] = 16.67 mL/hr Infusion rates: 33.33 mL/hr for 6 hours, then 16.67 mL/hr

Normal serum creatinine levels are 0.6 – 1.2 mg/dL.

Section: (none)

Explanation

Since LN used 3 mg of hydromorphone, this would be equivalent to a total of morphine 60 mg po daily. Since you would start with 70-80% of that dose, Morphine 15mg ER po q12hr and morphine 5mg po q6h prn breakthrough pain would be appropriate regimen.

A, B, C. Hepatotoxicity, including hepatic failure, has been fatal and may more commonly occur in the first 6 months of treatment. Valproic acid and its analogs are contraindicated in patients with known urea cycle disorders. Patients with urea cycle disorders have a genetic enzyme defect leading to an impaired ability to produce urea. Hyperammonemic encephalopathy has been reported following initiation of valproate therapy. Because of, inhibition of the secondary phase of platelet aggregation, and abnormal coagulation parameters complete blood counts and coagulation tests are recommended before initiating valproic acid therapy and at periodic intervals.

Cimetidine has multiple drug interactions due to its inhibitory effects on CYP1A2, 2C9, 2D6, and 3A4. Inhibition of these enzymes can cause an increase in the serum concentrations of drugs metabolized by these enzymes, leading to toxicity.

Pregnancy test. Tetracyclines are effective in the treatment of severe cases of acne. They are however teratogenic. As such, it is imperative to make sure female patients are not pregnant prior to starting this medication. In many instances patients are started on concurrent birth control to mitigate this risk even further.

A chest x-ray (B) is an important exam to obtain prior to starting drugs which have pulmonary toxicity as a side effect such as amiodarone. A complete blood count (C) would be useful prior to starting a medication that causes anemia, such as immunosuppressive and chemotherapeutic agents. Liver function tests (D) are important to establish as a baseline prior to starting anti-mycobacterial agents. Creatine kinase levels (E) are used to establish as a baseline prior to starting statins.

Section: (none)

Explanation

The direct Coombs test is used to test for autoimmune hemolyticanemia – a condition in which the body attacks red blood cells, leading to anemia. Some drugs can cause a positive direct Coombs test – methyldopa being one of the most well-known (via IgG-mediated type II hypersensitivity reaction). Other drugs that can cause this effect include quinidine (IgM-mediated activation) and penicillins (at very high doses).

Cisplatin. All chemotherapeutics have similar generalized side effects related to their effects on rapidly growing cells. These include hair loss, nausea, and fatigue. However, many chemotherapeutics have unique toxicities as well which are often tested. Cisplatin (C) is notable for its nephrotoxicity and ototoxicity. Cyclophosphamide

(A) is known to cause hemorrhagic cystitis. This is a distinct process from nephrotoxicity. The most noteworthy side effect of bleomycin (B) is pulmonary toxicity that can lead to pulmonary fibrosis. Vinblastine (D) is known for bone marrow suppression. Vincristine (E) causes neuropathy.

It is reasonable to add triglyceride-lowering medications such as fibrates or niacin to prevent pancreatitis in those with triglyceride levels >500 mg/dL, which applies to this patient as his TG level is 640 mg/dL . C. is wrong because gemfibrozil should not be initiated in patients on statin therapy because of an increased risk for muscle symptoms and rhabdomyolysis. Fenofibrate may be considered concomitantly with a low- or moderate- intensity statin when triglycerides are above 500 mg/dL,2, however he is on a high intensity statin therapy. For niacin, the IR dose should start at 100 mg TID2 and niacin does not lower triglyceride levels as much as fibrate do.4 Fenofibrates are dose adjusted for renal function lower than 60 mL/min to 54 mg/mL, so this dose is appropriate for this patient because of his renal function being above 60 mL/min. The best option is fenofibrate 162 mg daily, but this needs to be monitored for any symptoms of muscle pain exhibited by the patient, especially as the patient is at a higher risk due to being a diabetic. Fish oil is not a first line agent to treat hypertriglyceridemia.

Statin therapy should be used as treatment in adults with primary LDL–C ?190 mg/dL and age over 21 years. Unless contraindicated, high-intensity statin therapy should be used.