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NCLEX drug classes and suffixes practice questions

20 free NCLEX-style pharmacology questions built on drug suffixes (-olol, -pril, -sartan, -statin and more), with the side effect that defines each class and the nursing action that follows.

Tap an answer to check it, or open "Show the answer and rationale" under each question. Every client is fictional. For exam practice only, not medical advice.

Question 1 of 20

A client with type 2 diabetes who takes glipizide started weekly semaglutide injections 3 weeks ago. Which report by the client requires the nurse's immediate follow-up?

  1. Constant, severe upper abdominal pain that goes through to the back
  2. Nausea after the first dose that has since eased off almost completely
  3. A reading of 66 mg/dL before lunch yesterday that came back up after juice
  4. Feeling full sooner and eating smaller meals
Show the answer and rationale

Answer: A

GLP-1 receptor agonists such as semaglutide carry a warning for acute pancreatitis, which presents as persistent, severe abdominal pain, sometimes radiating to the back, with or without vomiting; the drug is stopped and the client is evaluated now. The low reading is the runner-up: adding a GLP-1 agonist to glipizide raises the risk of hypoglycemia and the glipizide dose may need to be lowered, but this low was treated and resolved. Decreased appetite and nausea are among the most common effects of the class and are expected.

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Question 2 of 20

A client who had a stroke receives continuous enteral feeding through a gastrostomy tube at 65 mL/hr and phenytoin oral suspension 100 mg three times daily through the tube. The phenytoin level is 6 mcg/mL, down from 13 mcg/mL before the feeding started, and the client had a brief seizure this morning. Which change in the plan of care should the nurse anticipate?

  1. Pausing the feeding for a set time before and after each dose of phenytoin
  2. Raising the phenytoin dose while the feeding runs unchanged around the clock
  3. Mixing each phenytoin dose into the feeding bag so it is absorbed evenly
  4. Changing to IV phenytoin pushed at 100 mg/min into a peripheral IV
Show the answer and rationale

Answer: A

Enteral formula binds phenytoin and cuts how much is absorbed, which explains a level that fell below the 10 to 20 mcg/mL range after the feeding started, so the feeding is held around each oral dose per protocol, with the tube flushed before and after, and the level is rechecked. A higher dose with the feeding unchanged may raise the level for now, but the level can climb into the toxic range when the feeding is later stopped or changed. Mixing the drug into the formula worsens the binding, and IV phenytoin is never given faster than 50 mg/min because rapid infusion can cause hypotension and dysrhythmias.

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Question 3 of 20

A 29-year-old client with type 2 diabetes who takes a combined oral contraceptive is starting weekly tirzepatide injections. Which statement by the client indicates understanding of the teaching?

  1. 'I'll use condoms too for 1 week after I start and after each dose increase.'
  2. 'The shot can't change how my pill works, since one is an injection and one is a pill.'
  3. 'I'll use condoms too for 4 weeks after I start and after each increase.'
  4. 'I'll take my pill at the same time as the shot so the two work together.'
Show the answer and rationale

Answer: C

Tirzepatide slows stomach emptying, which can reduce absorption of oral contraceptives, so the label advises a non-oral method or an added barrier method for 4 weeks after starting and for 4 weeks after each dose increase. The runner-up is using condoms for 1 week: the method is right, but the duration is too short to cover the absorption effect. An injection can affect a pill because the interaction happens in the gut, and taking the pill at the same time as the shot does not prevent the delayed absorption.

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Question 4 of 20

A client with osteoporosis has a new prescription for alendronate 70 mg once weekly. Which statement by the client indicates understanding of the teaching?

  1. 'I'll take it with plain water when I get up and stay upright for 30 minutes.'
  2. 'I'll take it with mineral water and wait 30 minutes before I eat.'
  3. 'I'll take it with plain water and my other morning pills, then sit upright.'
  4. 'I'll take it with plain water at bedtime, then lie down flat for the night.'
Show the answer and rationale

Answer: A

Alendronate is taken on waking with 6 to 8 oz of plain water, at least 30 minutes before food, other drinks or medicines, staying upright at least 30 minutes, because it can severely irritate the esophagus and is poorly absorbed. The runner-up is mineral water with a 30-minute wait: the timing is right, but the label specifies plain water because mineral water and other drinks reduce absorption. Taking it with other morning pills also blocks absorption, and a bedtime dose followed by lying flat leaves the tablet against the esophagus, risking ulceration.

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Question 5 of 20

A 74-year-old client with coronary artery disease started levothyroxine for hypothyroidism 2 months ago, and the dose was increased 3 weeks ago. Which finding requires the nurse's immediate follow-up?

  1. Still feeling more tired than usual by late afternoon each day
  2. Constipation and dry skin that are slowly getting better
  3. Takes the tablet with water at 0600 and eats breakfast at 0700
  4. Chest tightness when climbing stairs over the past week
Show the answer and rationale

Answer: D

Too much thyroid hormone speeds the heart and raises its oxygen demand, and older clients with heart disease are especially sensitive to it, so new chest tightness on exertion after a dose increase can be angina and is reported now. Lingering fatigue is the runner-up because it may mean the dose is still too low, but it is not dangerous and is judged with the next thyroid tests. Improving constipation and dry skin show the hormone is working, and taking the tablet with water an hour before breakfast is the correct routine.

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Question 6 of 20 · Select all that apply

A 79-year-old client who weighs 70 kg (154 lb) is on day 7 of IV gentamicin every 8 hours for a Pseudomonas infection. Which findings should the nurse report to the provider? Select all that apply.

  1. Temperature of 98.8°F (37.1°C), down from 101.6°F (38.7°C) on admission
  2. Numbness of the skin and twitching of the muscles in the hands
  3. Urine output of 120 mL over the past 8 hours
  4. Peak level of 6 mcg/mL drawn 30 minutes after the infusion ended
  5. Trough level of 0.8 mcg/mL drawn just before the last dose
  6. Dizziness and an unsteady, wide-based gait when walking to the bathroom
Show the answer and rationale

Answer: B, C, F

Dizziness and an unsteady gait signal damage to the vestibular part of the ear, and numbness, skin tingling and muscle twitching are nerve effects named in the gentamicin label warnings; ear damage from aminoglycosides is usually permanent, so these are reported at once. Urine output of 120 mL in 8 hours, 15 mL/hr in a 70-kg client, is oliguria and can mean kidney injury, and advanced age adds to the risk. A trough of 0.8 mcg/mL is below the 2 mcg/mL the label says to avoid exceeding, a peak of 6 mcg/mL is well under the 12 mcg/mL limit, and the falling temperature shows the infection is responding.

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Question 7 of 20

A 72-year-old client is on day 4 of IV vancomycin every 12 hours for a methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infection. The 2100 dose is due. Which finding should the nurse report to the provider before giving the dose?

  1. Flushing of the neck during the last dose that faded when the rate was slowed
  2. Redness and tenderness along the vein above the peripheral IV site
  3. Serum creatinine of 1.9 mg/dL, up from 0.9 mg/dL 2 days ago
  4. White blood cell count of 10,900/mm³, down from 17,400/mm³
Show the answer and rationale

Answer: C

A creatinine that has more than doubled in 2 days meets the definition of acute kidney injury, and the vancomycin label warns that the risk of kidney injury rises as drug exposure rises, so the nurse reports it before the dose and the provider and pharmacy adjust the dose to kidney function and a drug level. Redness along the vein is phlebitis, a known effect of vancomycin that calls for a new IV site, but it does not change the dose. Flushing that settled with a slower rate was an infusion reaction managed by infusing over a longer time, and a falling white cell count shows the infection is responding.

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Question 8 of 20

A nurse reviews postoperative pain prescriptions for four clients. Which prescription should the nurse clarify with the provider?

  1. Fentanyl PCA with higher-than-usual demand doses for a client who takes methadone daily for opioid use disorder
  2. Morphine PCA for a client whose listed codeine allergy was nausea and vomiting
  3. Hydromorphone PCA with a basal rate for an opioid-naive 72-year-old with sleep apnea
  4. Morphine PCA for a 15-year-old on the first day after spinal fusion surgery
Show the answer and rationale

Answer: C

A continuous basal infusion keeps delivering opioid even after a client becomes too sedated to press the button, which removes the PCA's built-in safety, so it is not recommended for opioid-naive adults, and this client's age and sleep apnea add to the risk of respiratory depression. A client on daily methadone is opioid-tolerant and usually needs larger doses than usual, so that order is expected. Nausea is a common side effect rather than a true allergy, and adolescents who understand how to use the button manage PCA well.

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Question 9 of 20

A client with a positive tuberculin skin test and a normal chest x-ray is starting isoniazid for latent tuberculosis infection. Which statement by the client indicates understanding of the teaching?

  1. 'A small glass of wine with dinner is fine if I take the pill early in the morning.'
  2. 'I'll take it with an antacid an hour before meals so it doesn't upset my stomach.'
  3. 'I'll take vitamin B6 with it and call if my skin or eyes look yellow.'
  4. 'I'll keep taking it for the full course, but I can stop the vitamin B6 after a month.'
Show the answer and rationale

Answer: C

Isoniazid depletes pyridoxine (vitamin B6), which causes peripheral neuropathy, so B6 is taken for the whole course, and the drug's main danger is liver injury, so yellowing of the skin or eyes is reported promptly and liver enzymes are checked as prescribed. The runner-up gets the full course right but stops B6 after a month, leaving the client unprotected against neuropathy for the remaining months. Alcohol is avoided because it adds to the liver risk, whatever time the pill is taken, and aluminum-containing antacids reduce isoniazid absorption, so the dose is taken on an empty stomach and separated from any antacid.

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Question 10 of 20

An 84-year-old client with chronic kidney disease and a creatinine clearance of 24 mL/min is admitted with pneumonia. On the third hospital day, the client is newly confused and restless. Temperature is 98.4°F (36.9°C), SpO2 is 96% on room air, and blood glucose is 112 mg/dL. Which prescription should the nurse discuss with the provider?

  1. Heparin 5,000 units subcutaneously every 8 hours
  2. Acetaminophen 650 mg by mouth every 6 hours as needed
  3. Famotidine 20 mg IV every 12 hours
  4. Ceftriaxone 1 g IV every 24 hours
Show the answer and rationale

Answer: C

Famotidine is cleared by the kidneys and builds up when creatinine clearance is low, and confusion and delirium have been reported in older adults and in clients with kidney impairment, so its dose is lowered or the drug is changed. Ceftriaxone draws suspicion because antibiotics are often blamed for new symptoms, but it needs no dose change for kidney function and is not a usual cause of confusion. Unfractionated heparin, unlike enoxaparin, does not depend on the kidneys for clearance, and acetaminophen at this dose is safe in kidney disease. The normal temperature, saturation and glucose make worsening infection, hypoxia and hypoglycemia less likely causes.

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Question 11 of 20

A client with type 2 diabetes was started on NPH insulin every morning in the hospital while taking prednisone 40 mg daily. The client is going home on a prednisone taper that lowers the dose every few days. Which statement by the client indicates understanding of the teaching?

  1. 'I'll check my sugar before breakfast each day, since that's when prednisone raises it most.'
  2. 'Once the prednisone dose drops below 20 mg a day, I'll stop checking my sugar every day.'
  3. 'As the prednisone goes down, my NPH will need to come down too, so I'll check my sugar more often.'
  4. 'I'll keep taking the same NPH dose each morning until the prednisone is completely finished.'
Show the answer and rationale

Answer: C

The NPH dose was matched to the glucose-raising effect of prednisone 40 mg daily; as the taper lowers the steroid, that effect fades, so insulin needs fall too and more frequent checks catch lows. The runner-up is keeping the same NPH dose until the prednisone ends: it sounds like following the prescription, but the unchanged dose invites hypoglycemia as the steroid drops. Morning prednisone raises glucose most in the afternoon and evening, not before breakfast, and cutting back on checks once the dose falls below 20 mg misses exactly the period when lows appear.

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Question 12 of 20

A 28-year-old client with a seizure disorder has taken phenytoin for 2 years. At a clinic visit, the client's gums are overgrown and bleed easily, and the phenytoin level is 14 mcg/mL. Which statement by the client indicates understanding of the teaching?

  1. 'I'll brush and floss gently every day and keep my dental visits.'
  2. 'My gums show the dose is too high, so I'll ask to have it lowered.'
  3. 'My gums should shrink back on their own once my body adjusts to the drug.'
  4. 'I'll use a soft brush but skip flossing until my gums stop bleeding.'
Show the answer and rationale

Answer: A

Gum overgrowth is a common effect of long-term phenytoin even at a therapeutic level, and 14 mcg/mL is within the usual 10 to 20 mcg/mL range, so the client keeps taking the drug and controls plaque with gentle daily brushing and flossing and regular dental care, which limits the overgrowth and its bleeding. Using a soft brush but skipping floss is the runner-up: it sounds gentle, but plaque left between the teeth inflames the gums and speeds the overgrowth. The overgrowth does not shrink while the drug continues; it may regress only after phenytoin is stopped, and severe cases need surgery. The gums do not signal a high dose, since toxicity shows as nystagmus, ataxia and slurred speech, and this level is therapeutic.

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Question 13 of 20

A client with type 2 diabetes who uses insulin glargine had pioglitazone added 2 months ago. Which finding requires the nurse's immediate follow-up?

  1. Weight up 5 lb (2.3 kg) in 4 days, with swollen ankles and shortness of breath when lying flat
  2. An A1C of 7.4%, down from 8.6% three months ago
  3. Mild ankle swelling at the end of the day that is gone by morning, with a stable weight
  4. A fasting glucose of 96 mg/dL this morning
Show the answer and rationale

Answer: A

Thiazolidinediones such as pioglitazone cause fluid retention, especially when combined with insulin, and can bring on or worsen heart failure, so rapid weight gain with swollen ankles and orthopnea is reported now, and the pioglitazone may be stopped or reduced. Mild ankle swelling that clears overnight with a stable weight is the runner-up, since it is the same side effect, but it shows no fluid building up. A fasting glucose of 96 mg/dL is in range, and a falling A1C shows the added drug is working.

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Question 14 of 20 · Select all that apply

A 66-year-old client who takes prednisone 10 mg daily for polymyalgia rheumatica is being discharged with levofloxacin 750 mg daily for 5 days. Which statements by the client indicate understanding of the teaching? Select all that apply.

  1. 'I'll take the levofloxacin 2 hours before or 2 hours after my antacid.'
  2. 'I'll call right away if my feet start to burn or tingle.'
  3. 'I'll skip my prednisone while I take the antibiotic so they don't interact.'
  4. 'A tanning bed is fine as long as I stay out of the sun.'
  5. 'If my heel cord hurts or swells, I'll stop the pills, rest the leg and call my provider.'
  6. 'Once I finish the last pill, my tendons are no longer at risk.'
Show the answer and rationale

Answer: A, B, E

Fluoroquinolones can inflame or rupture tendons, and the risk is higher after age 60 and with corticosteroids, so at the first sign of tendon pain or swelling the client stops the drug, rests the area and calls the provider. Antacids and supplements with magnesium, aluminum, iron or zinc block absorption, so the dose is taken 2 hours before or after them, and burning or tingling in the feet can signal nerve damage that may become permanent. Tendon rupture can occur months after the last dose, stopping prednisone abruptly can cause adrenal crisis, and tanning beds, like sunlight, can cause severe sunburn.

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Question 15 of 20

A 62-year-old man with type 2 diabetes who started empagliflozin 3 months ago calls the clinic. Which report requires the nurse's immediate follow-up?

  1. 'I've felt lightheaded twice this week when I stood up quickly from a chair.'
  2. 'I'm urinating a lot more often than before, and I get up once or twice at night.'
  3. 'The head of my penis has been red and itchy, with a white discharge, for a few days.'
  4. 'The area between my scrotum and anus is swollen and very painful, and I have a fever.'
Show the answer and rationale

Answer: D

Pain, tenderness, redness or swelling of the genital or perineal area with fever or malaise in a client taking an SGLT2 inhibitor can be necrotizing fasciitis of the perineum (Fournier's gangrene), a serious, potentially fatal infection that needs urgent evaluation; the drug is stopped and treatment started. Lightheadedness on standing is the runner-up, since these drugs can cause volume depletion, but two brief episodes need follow-up that is less urgent. Redness and itching of the penis suggest a genital yeast infection, a common effect that needs treatment, and more frequent urination is expected.

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Question 16 of 20

A client is to receive gentamicin 120 mg IV every 8 hours, infused over 30 minutes. The 0900 dose is hung on time and finishes at 0930, and a peak level is prescribed with this dose. At what time should the nurse have the peak level drawn?

  1. 0845
  2. 1000
  3. 0930
  4. 1030
Show the answer and rationale

Answer: B

A peak level after an IV infusion is drawn about 30 minutes after the infusion ends, once the drug has spread through the tissues, so for a dose that finishes at 0930 the peak is drawn at 1000. Drawing it at 0930, the moment the infusion ends, is the tempting choice, but it catches a falsely high level that could lead to an unneeded dose cut. 0845 is the timing of a trough, which is drawn just before a dose, and at 1030 the level is already falling, which can make the dose look too low. The label says to avoid peaks that stay above 12 mcg/mL and troughs above 2 mcg/mL.

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Question 17 of 20

A 74-year-old client with community-acquired pneumonia has a new prescription for levofloxacin 750 mg by mouth once daily. Which finding in the client's history should the nurse report to the provider before the first dose?

  1. An abdominal aortic aneurysm checked by yearly ultrasound
  2. Acetaminophen taken twice daily for knee arthritis
  3. Hives after a dose of amoxicillin 10 years ago
  4. A daily multivitamin that contains iron and zinc
Show the answer and rationale

Answer: A

Fluoroquinolones raise the risk of aortic aneurysm rupture and dissection, and FDA labeling tells clients to report a known aortic aneurysm and advises avoiding these drugs in such clients unless no other treatment fits, so the nurse reports it before the first dose. The multivitamin is a real interaction, but it is managed by taking levofloxacin 2 hours before or 2 hours after products with iron, zinc, magnesium or aluminum. A penicillin allergy does not cross-react with a fluoroquinolone, and acetaminophen, unlike an NSAID, does not add to the risk of seizures and other central nervous system effects.

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Question 18 of 20

A 71-year-old client who takes omeprazole daily finished a 7-day course of levofloxacin for pneumonia 5 weeks ago. The client calls the clinic to report 6 watery stools a day for the past 2 days, with cramping and a temperature of 100.6°F (38.1°C). Which response by the nurse is best?

  1. 'The antibiotic left your body weeks ago, so this is most likely a stomach virus.'
  2. 'This can still come from the antibiotic, so you need to be seen today.'
  3. 'Take an over-the-counter antidiarrheal and call back if it lasts beyond 3 days.'
  4. 'Drink plenty of fluids and eat yogurt with live cultures until the stools firm up.'
Show the answer and rationale

Answer: B

Clostridioides difficile infection can begin during an antibiotic course or 2 or more months after it ends, and daily acid suppression with a proton pump inhibitor adds to the risk, so frequent watery stools with cramping and fever call for an evaluation today with a stool test. Fluids and yogurt sound supportive, but they leave a possibly serious infection untreated. Blaming a virus ignores the timeline the levofloxacin label describes, and an antidiarrheal while waiting 3 days delays the diagnosis.

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Question 19 of 20

A 58-year-old client with gastroesophageal reflux disease has a new prescription for omeprazole 20 mg daily. Which statement by the client indicates understanding of the teaching?

  1. 'I'll take it only when heartburn starts, because it works in minutes.'
  2. 'I can take it for years, since it has no long-term risks.'
  3. 'I'll take it 30 to 60 minutes before breakfast.'
  4. 'I'll take it with my bedtime snack so it works through the night.'
Show the answer and rationale

Answer: C

Proton pump inhibitors block the acid pumps that a meal switches on, so omeprazole works best taken 30 to 60 minutes before breakfast. Taking it at bedtime with a snack sounds logical for night symptoms, but it misses the pumps that turn on with the first meal of the day. A proton pump inhibitor takes days to reach its full effect and gives no quick relief, and long-term use raises the risk of fractures, Clostridioides difficile infection and low magnesium and vitamin B12 levels, so the need for it is reviewed regularly.

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Question 20 of 20

A client has a first episode of Clostridioides difficile infection with 8 watery stools a day. The prescription reads 'vancomycin 125 mg IV every 6 hours.' What should the nurse do?

  1. Pour the IV solution into water and give the dose by mouth instead
  2. Give the dose IV over at least 60 minutes to prevent a reaction
  3. Contact the provider, because the drug must be given by mouth
  4. Hold the dose and give IV metronidazole instead for this first episode
Show the answer and rationale

Answer: C

Oral vancomycin stays in the bowel and reaches high levels where C. difficile grows, while IV vancomycin does not reach the colon in useful amounts, so the prescription is clarified with the provider; oral vancomycin 125 mg four times daily or fidaxomicin is standard for a first episode. The runner-up pours the IV solution by mouth, which aims at the right route, but a nurse cannot change the route or formulation of a prescription independently; an oral product is prepared by pharmacy under a clarified order. IV metronidazole is not a first-line substitute for a first episode, and infusing the dose slowly over 60 minutes does not solve the route problem, since the drug still never reaches the colon.

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