NAPLEX Exam Questions and Answers | Exam-Dumps (Page: 4)

QUESTION: 16

Which of the following statements is true regarding Drug-receptor bonds?

Covalent bonds of drugs with receptors are strong and mostly reversible
Covalent bonding is much more common than electrostatic bonding in drug-receptor interactions
Electrostatic bonds are stronger than covalent bonds
Hydrophobic bonds are weak bonds and they are important in the interactions of highly water soluble drugs with the lipids of cell membranes
Bond formation of between the acetyl group of aspirin and cyclo-oxygenase enzyme is a covalent bond

Answer(s): E

Explanation:

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”.

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QUESTION: 17

Which of the following NSAIDs is an Enolic acid derivative?

Ibuprofen
Piroxicam
Naproxen
Oxaprozin
Fenoprofen

Answer(s): B

Explanation:

The following NSAIDs belong to the propionic acid derivatives group - Ibuprofen - Ketoprofen - Naproxen - Fenoprofen - Flurbiprofen - Oxaprozin whereas piroxicam belongs to the class of Enolic acid derivative which also includes other agents like meloxicam and Nabumetone. They are non- selective COX inhibitors and act by preventing the production of certain prostaglandins.

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QUESTION: 18

A 67-year-old female presents to your clinic complaining of fatigue, diarrhea, headaches and a loss of appetite. Upon examination you find that she is having some cognitive difficulty. Laboratory results reveal: MCV: 109fL; Hgb: 9g/dL; MMA and homocystine are both elevated. Shilling test is positive.
What is the next best step in the management of this patient?

Lifelong folic acid supplementation
Lifelong Vitamin B12 supplementation
Iron supplementation for 4-6 months
Obtain a Coomb’s test
Give corticosteroids and iron supplementation

Answer(s): B

Explanation:

Lifelong Vitamin B12 supplementation. Vitamin B12 (cyanocobalamin) deficiency generally presents in patients as fatigue, diarrhea and headaches but can also be the cause of cognitive changes (difficulty concentrating, even mild dementia). Pernicious anemia is a macrocytic anemia, therefore laboratory findings indicate an increased mean corpuscular volume (MCV), with a decreased hemoglobin. A positive Schilling test indicates that the B12 deficiency is due to a lack of intrinsic factor. Lifelong cyanocobalamin supplementation (either orally or via injections) is needed to treat pernicious anemia. A is incorrect. Folic acid deficiency anemia is another common type of macrocytic anemia. However, cognitive deficits are not typically seen with folic acid deficiency. Furthermore, a schilling test would be negative and the methylmalonic acid (MMA) would be normal, rather than elevated. C is incorrect. Iron deficiency anemia causes a microcytic anemia, characterized by a decreased MCV. D is incorrect. A Coomb’s test is used to detect autoimmune hemolysis that may be suspected in patients with normocytic anemia (anemia with an MCV in the normal range). E is incorrect. Corticosteroids and iron supplementation are indicated as treatment in hemolytic anemia.

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QUESTION: 19

Your patient, a 25-year-old G1P0 female at 26 weeks gestation presents due to an abnormal glucose tolerance test. One week prior, she was given 50 g of oral glucose and demonstrate a venous plasma glucose level of 156 mg/dL one hour later.
Which of the following is the most appropriate next step of management?

Repeat the 50 g oral glucose challenge
Administer an oral, 3-hour 100 g glucose dose
Advise the patient to follow an American Diabetic Association diet plan
Begin insulin treatment
Order a fetal ultrasound examination

Answer(s): B

Explanation:

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).

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QUESTION: 20

A 23-year-old female presents to your clinic complaining of intermittent throbbing headaches that usually last for several hours and are made worse by the presence of light. She endorses occasional nausea without vomiting during the most severe episodes. Physical examination is unrevealing, and she has no significant past medical history.
Which of the following treatments is considered an abortive therapy for this patient’s underlying condition?

Sumatriptan
Gabapentin
Amitriptyline
Propranolol
Diltiazam

Answer(s): A

Explanation:

Correct: A. Migraine headaches typically affect females more often than males, and patients most frequently present in their early 20s. Classic symptoms of migraine include throbbing headaches lasting between 2–24 hours in duration, with triggers such as red wine, fasting, stress, and menses. Primary prevention is aimed at the identification and avoidance of triggers. Over the counter NSAIDS can be used if symptoms persist. Failing this, PRN abortive therapy is indicated, including the triptans (e.g. – sumatriptan) and metoclopramide. Choice B – Gabapentin is an anticonvulsant that is considered to be a second-line, prophylactic treatment for recurrent migraine headaches. Its utility is limited by its lengthy side effect profile. Choice C – Amitriptyline, a tricyclic antidepressant, can also be utilized for migraine prophylaxis. However, it will not abort a migraine currently in progress, and extensive side effects limit its use. Choices D + E – Propranolol and diltiazam are beta-blockers and calcium channel blockers, respectively. As with the anticonvulsants and tricyclic antidepressants, these are considered migraine prophylaxis and will not interrupt a migraine once it has begun.

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Test Prep NAPLEX Exam (page: 4) Test Prep North American Pharmacist Licensure Examination Updated on: 25-Dec-2025

QUESTION: 16

Explanation:

QUESTION: 17

Explanation:

QUESTION: 18

Explanation:

QUESTION: 19

Explanation:

QUESTION: 20

Explanation:

Test Prep NAPLEX Exam (page: 4)
Test Prep North American Pharmacist Licensure Examination
Updated on: 25-Dec-2025