HESI Pharmacology IV Exam

Correct answer B: 10 to 20 mcg/mL

Explanation of the correct answer:

B. 10 to 20 mcg/mL

Phenytoin (Dilantin) is an anticonvulsant used to manage and prevent seizures. It has a narrow therapeutic index, which means that blood levels must be carefully monitored to ensure effectiveness without causing toxicity. The therapeutic serum level for phenytoin is 10 to 20 mcg/mL. Within this range, the drug is typically effective in controlling seizures while minimizing the risk of side effects. Levels below 10 mcg/mL may result in inadequate seizure control, while levels above 20 mcg/mL increase the risk for toxicity, which can cause symptoms such as nystagmus, ataxia, slurred speech, confusion, lethargy, and potentially life-threatening cardiac arrhythmias.

Why the other options are incorrect:

A. 5 to 10 mcg/mL

This range is below the therapeutic level and may be insufficient to control seizures, putting the client at risk for breakthrough seizure activity.

C. 20 to 30 mcg/mL

This range is above the therapeutic level and increases the risk for phenytoin toxicity. Levels greater than 20 mcg/mL can lead to central nervous system and cardiovascular side effects.

D. 30 to 40 mcg/mL

This range is considered toxic and poses a serious risk to the client. At this level, immediate medical intervention is necessary to prevent life-threatening complications.

Summary:

A serum phenytoin level between 10 to 20 mcg/mL is considered therapeutic and safe for most clients. Monitoring this range is essential for ensuring the medication is both effective and non-toxic.

Correct answer C: Proceed to the closest emergency room.

Explanation of the correct answer:

Danazol (Danocrine) is a synthetic steroid used to treat conditions like endometriosis. One of the serious side effects of danazol is an increased risk of deep vein thrombosis (DVT), which can present with symptoms such as dark, swollen, and painful legs. These symptoms are indicative of a potential blood clot in the leg, which is a medical emergency because a clot can travel to the lungs (pulmonary embolism) or other organs, which could be life-threatening. Therefore, the client should immediately seek medical care by going to the emergency room for further evaluation and treatment.

Why the other options are incorrect:

A. Wear support stockings:

While support stockings can help with circulation, they are not appropriate or effective for managing a possible DVT. In fact, using them without addressing the underlying problem of a clot could delay the proper treatment and diagnosis.

B. Elevate both legs and apply heat:

Elevating the legs and applying heat may provide temporary relief for minor swelling or discomfort, but they do not address the potential DVT. Applying heat to a clot could actually increase the risk of the clot dislodging, which could lead to a serious complication like a pulmonary embolism.

D. Walk for 20 to 30 minutes to reduce the pain and edema:

Walking could potentially worsen the situation if there is a clot present. Exercise or movement could cause the clot to dislodge, increasing the risk of it traveling to the lungs or other vital organs. Therefore, walking is not recommended in this scenario.

Summary:

The client’s symptoms of dark, swollen, and painful leg could indicate a deep vein thrombosis (DVT), a potentially serious side effect of danazol. The client should be instructed to proceed to the closest emergency room immediately for further evaluation and management of the possible clot.

Correct Answer D: Orthostatic hypotension

Explanation of the Correct Answer:

D. Orthostatic hypotension is correct because etoposide (VePesid), an antineoplastic medication commonly used in the treatment of small cell lung cancer (SCLC), is known to cause orthostatic hypotension as a potential side effect. This can occur due to the drug's effects on the autonomic nervous system, leading to a decrease in blood pressure when the client changes position from lying down to standing up. The nurse should monitor the client closely for signs of dizziness, lightheadedness, or fainting, especially after changing positions, and encourage the client to rise slowly from a seated or lying position to minimize the risk.

Why the other options are incorrect:

A. Alopecia is incorrect because although alopecia is a common side effect of many chemotherapy medications, it is not specifically associated with etoposide. While hair loss can occur, it is not as prominent or distinctive as some other side effects seen with other chemotherapeutic agents.

B. Chest pain is incorrect because chest pain is not a well-known or common side effect of etoposide. While cancer itself or other treatments like radiation may cause chest discomfort, etoposide does not typically cause chest pain directly.

C. Pulmonary fibrosis is incorrect because pulmonary fibrosis is not specifically associated with etoposide. Although some chemotherapy agents, such as bleomycin, are linked to pulmonary toxicity, etoposide is more commonly associated with hematologic toxicities, including leukopenia, and cardiovascular side effects like orthostatic hypotension, but not pulmonary fibrosis.

Summary:

The nurse assisting in the care of a client receiving etoposide should be particularly aware of the risk for orthostatic hypotension, which is a known side effect of the drug. Monitoring for signs of dizziness or fainting upon standing and encouraging safe practices when changing positions are key nursing interventions. While alopecia, chest pain, and pulmonary fibrosis can occur with other treatments, they are not specifically associated with etoposide therapy.

Correct answer C: Serum amylase

Explanation of the correct answer:

C. Serum amylase

Didanosine (Videx), an antiretroviral medication used in the treatment of HIV/AIDS, is associated with an increased risk of pancreatitis. Elevated serum amylase is a key indicator of pancreatic dysfunction, and if this level becomes significantly elevated, the healthcare provider may consider discontinuing the medication. Pancreatitis is a serious and potentially life-threatening side effect of didanosine, and monitoring serum amylase levels is essential to detect this condition early.

Why the other options are incorrect:

A. Serum protein

While serum protein levels can provide useful information about the overall nutritional status and liver function, elevated serum protein is not a typical cause for discontinuing didanosine therapy. Serum protein is not directly related to the risk of pancreatitis caused by didanosine.

B. Blood glucose

Blood glucose levels can be affected by many factors, including certain medications, but didanosine does not typically cause significant hyperglycemia or hypoglycemia to the extent that it would require discontinuation. Blood glucose monitoring is important in some situations, but it is not the most relevant factor for stopping didanosine.

D. Serum creatinine

Serum creatinine is primarily used to assess renal function, and although didanosine can have renal side effects, it is not as strongly associated with renal failure as it is with pancreatitis. An elevated serum creatinine would require investigation, but it is the serum amylase level that is more specifically linked to the risk of pancreatitis with didanosine use.

Summary:

If serum amylase is significantly elevated in a client taking didanosine (Videx), it could indicate pancreatitis, a serious side effect of the medication. In this case, the healthcare provider may decide to discontinue the medication. Monitoring serum amylase is crucial in detecting this potential complication.

Correct Answer:

A. Nizatidine (Axid),

B. Ranitidine (Zantac),

C. Famotidine (Pepcid),

D. Cimetidine (Tagamet)

Explanation of the Correct Answer:

A. Nizatidine (Axid)

Nizatidine is classified as an H2-receptor antagonist. H2-receptor antagonists work by blocking the action of histamine on the H2 receptors found in the parietal cells of the stomach. Histamine normally stimulates these cells to produce gastric acid. By inhibiting this action, nizatidine reduces gastric acid secretion, thus providing relief from conditions like GERD, peptic ulcers, and gastritis. It is used to treat heartburn, acid reflux, and ulcers, and to prevent stomach damage from NSAIDs.

B. Ranitidine (Zantac)

Ranitidine, another H2-receptor antagonist, functions similarly to nizatidine. It blocks H2 histamine receptors on the parietal cells, resulting in a reduction in gastric acid secretion. This mechanism of action helps reduce symptoms of acid reflux and can aid in healing gastric and duodenal ulcers. Ranitidine is also used to prevent and treat GERD and Zollinger-Ellison syndrome, where excess stomach acid is produced. Due to its widespread use, ranitidine has been historically used to manage heartburn and peptic ulcers.

C. Famotidine (Pepcid)

Famotidine, like nizatidine and ranitidine, is also an H2-receptor antagonist. It reduces the secretion of stomach acid by blocking histamine's action at the H2 receptors on parietal cells in the stomach. Famotidine is commonly used to treat GERD, gastric ulcers, and duodenal ulcers. It also aids in treating conditions such as hypersecretory states like Zollinger-Ellison syndrome. Famotidine is more potent than some other H2 blockers, and it provides longer-lasting relief from acid-related conditions.

D. Cimetidine (Tagamet)

Cimetidine is one of the first H2-receptor antagonists developed and works in the same way as the other medications listed above, by inhibiting histamine from binding to the H2 receptors in the stomach’s parietal cells. This results in reduced gastric acid production. Cimetidine is used for treating gastric ulcers, GERD, and peptic ulcers. However, cimetidine has some important drug interactions due to its effect on liver enzymes, particularly cytochrome P450 enzymes, which can interfere with the metabolism of other medications.

Why the Other Options Are Incorrect:

E. Esomeprazole (Nexium)

Esomeprazole is not an H2-receptor antagonist. It is a proton pump inhibitor (PPI), which works by inhibiting the H+/K+ ATPase pump (also called the proton pump) in the parietal cells of the stomach. This inhibition prevents the final step in the production of gastric acid. PPIs, including esomeprazole, are generally more potent than H2 blockers and provide a longer duration of acid suppression. PPIs like esomeprazole are used to treat GERD, gastric ulcers, H. pylori infection in combination with antibiotics, and conditions like Zollinger-Ellison syndrome. While both PPIs and H2 blockers reduce gastric acid, they act on different mechanisms within the gastric parietal cells.

F. Lansoprazole (Prevacid)

Lansoprazole is also a proton pump inhibitor (PPI), not an H2-receptor antagonist. As a PPI, lansoprazole works by blocking the proton pump in the stomach lining, which is responsible for the production of gastric acid. This results in stronger and longer-lasting acid suppression compared to H2-receptor antagonists. Lansoprazole is used for the treatment of GERD, peptic ulcers, and gastritis. It is also used as part of combination therapy for treating H. pylori infections.

Summary:

H2-receptor antagonists, including nizatidine, ranitidine, famotidine, and cimetidine, work by blocking histamine receptors in the stomach, leading to a reduction in gastric acid secretion. These medications are used to treat conditions such as GERD, peptic ulcers, and gastritis. In contrast, proton pump inhibitors (PPIs), such as esomeprazole and lansoprazole, work by inhibiting the proton pump, which is the final step in the gastric acid production process, providing more powerful and sustained acid suppression.

Correct answer C: Daily weight gain of 2 pounds

Explanation of the correct answer:

C. Daily weight gain of 2 pounds

Disopyramide (Norpace) is a Class Ia antidysrhythmic agent with significant negative inotropic effects, meaning it can weaken the force of the heart's contraction. Because of this, it can exacerbate or precipitate congestive heart failure (CHF), especially in clients with preexisting cardiac dysfunction. A daily weight gain of 2 pounds is a key early sign of fluid retention and worsening heart failure. This symptom should be immediately reported, as it may indicate that the medication is negatively impacting the client’s cardiac function, requiring prompt reassessment of therapy.

Why the other options are incorrect:

A. Joint pain

Joint pain is not a known or serious adverse effect of disopyramide and is unlikely to be related to the medication. It does not signal a cardiac or systemic emergency related to this drug.

B. Dizziness or muscle weakness

While dizziness or weakness can occur with many cardiac medications due to hypotension or bradycardia, these are not specific red flags for disopyramide toxicity or worsening heart failure in the way that weight gain is. Additionally, muscle weakness alone is not commonly a hallmark of disopyramide-induced complications.

D. Dry mouth

Dry mouth is a common and expected side effect due to disopyramide’s strong anticholinergic properties. Although it can be uncomfortable, it is not harmful and does not require discontinuation of therapy unless it severely affects quality of life or leads to complications.

Summary:

A daily weight gain of 2 pounds may indicate fluid overload and early signs of heart failure, a significant adverse effect of disopyramide. This finding requires prompt medical evaluation and possible adjustment of therapy. Other symptoms like dry mouth and joint pain are either expected or not significant in this context.

Correct answer D: Take the medication when consuming food.

Explanation of the correct answer:

Pancrelipase (Pancrease) is a pancreatic enzyme replacement therapy used to help clients with chronic pancreatitis digest food. The medication contains enzymes (lipase, amylase, and protease) that aid in the breakdown of fats, carbohydrates, and proteins, which people with chronic pancreatitis may struggle to digest due to insufficient pancreatic enzyme production. It is most effective when taken with food because the enzymes need to be present in the digestive tract during food intake to aid in the digestive process. The nurse should instruct the client to take pancrelipase just before or with meals and snacks to optimize its action.

Why the other options are incorrect:

A. Avoid prolonged exposure to direct sunlight:

This instruction is typically relevant for certain medications that cause photosensitivity (such as some antibiotics), but it is not a known side effect of pancrelipase. Therefore, this is not the most important teaching point.

B. Stay away from products containing alcohol:

Although alcohol can exacerbate chronic pancreatitis and worsen pancreatic damage, it is not a specific concern for pancrelipase. However, advising clients with chronic pancreatitis to limit alcohol intake is generally recommended, but it is not directly related to the use of pancrelipase.

C. Ingest 8 oz of grapefruit juice with the medication:

There is no evidence suggesting that grapefruit juice should be taken with pancrelipase. Grapefruit juice can interact with certain medications, altering their metabolism, but it does not have a known beneficial effect on pancrelipase or its efficacy.

Summary:

The most important instruction is to take pancrelipase with food. This ensures the enzyme is available in the digestive tract during food consumption, helping to improve digestion and reduce symptoms associated with chronic pancreatitis, such as malabsorption and weight loss.

Correct Answer A: Hyperventilation

Why A is correct:

Hyperventilation is a key indicator of systemic toxicity from mafenide acetate (Sulfamylon) because this medication can be absorbed through burn tissue and may lead to metabolic acidosis. Metabolic acidosis occurs when the body accumulates too much acid or loses too much base, and one of the body’s compensatory mechanisms is to increase respiratory rate in order to eliminate carbon dioxide, which is acidic. Therefore, the nurse must recognize hyperventilation as a sign that the client may be developing metabolic acidosis due to systemic absorption of mafenide acetate. This symptom requires immediate intervention such as notifying the provider and discontinuing the medication, because continued administration in the presence of acidosis can lead to worsening acid-base imbalance and severe complications. The recognition of hyperventilation as a systemic sign is critical for early detection and prevention of further toxicity.

Why B is incorrect:

Elevated blood pressure is not a recognized systemic effect of mafenide acetate. This medication primarily affects acid-base balance rather than cardiovascular tone. While stress or pain from the burn injury or its treatment could theoretically elevate blood pressure, such a finding would not be specific to mafenide acetate toxicity and would not help the nurse identify systemic absorption of the medication. Therefore, this option does not accurately reflect the known systemic effects associated with this drug.

Why C is incorrect:

Local pain at the burn site is a common and expected effect of topical mafenide acetate. It often causes a burning or stinging sensation on application, particularly to partial-thickness burns. This reaction is due to the irritating properties of the drug on nerve endings in the injured tissue. While uncomfortable for the patient, local pain does not indicate systemic absorption and is not considered a toxic effect. Nurses typically monitor for worsening pain, but isolated pain at the application site without systemic symptoms is not a reason to suspect toxicity.

Why D is incorrect:

A local rash at the burn site may suggest a hypersensitivity or allergic reaction to the medication, but it is still a localized response and not indicative of systemic toxicity. Systemic toxicity involves broader physiological effects, such as changes in respiratory pattern, mental status, or acid-base balance. A rash would be treated with discontinuation of the medication and potentially switching to an alternative topical agent, but it would not signal metabolic acidosis or require the same urgent systemic assessment as hyperventilation.

Summary:

Mafenide acetate is a topical antimicrobial agent used in burn care that is known to be systemically absorbed through damaged tissue. One of its serious systemic effects is the development of metabolic acidosis. The earliest and most recognizable sign of this complication is hyperventilation, as the body attempts to correct the acidosis by exhaling more carbon dioxide. Hyperventilation should alert the nurse to stop the medication and notify the provider immediately. Local pain or rash are expected localized effects, and elevated blood pressure is not associated with this medication's systemic toxicity profile. Therefore, the correct answer is A. Hyperventilation.

Correct answer A: Do not crush the tablet prior to administration.

Explanation of the correct answer:

Topiramate tablets should not be crushed because doing so can alter the medication's effectiveness and lead to an increased risk of side effects. Some forms of topiramate are extended-release formulations, and crushing the tablet could result in the rapid release of the medication, potentially leading to a higher-than-intended dose. This could increase the risk of side effects, such as dizziness, drowsiness, or even an overdose. Therefore, the nurse should advise the parents to avoid crushing the tablet and to give it as prescribed.

Why the other options are incorrect:

B. Give the medication with 8 oz of orange juice:

Topiramate does not require being taken with orange juice specifically. It can be taken with or without food or liquids, and there is no known interaction between orange juice and topiramate that would require special instructions.

C. Avoid prolonged exposure to direct sunlight:

While this is a helpful general advice for certain medications that cause photosensitivity, topiramate does not significantly increase photosensitivity, so this is not a primary concern. Parents should be educated on the usual side effects, but this is not a top priority for topiramate.

D. Administer the tablet an hour before meals:

Topiramate does not require specific timing related to meals. It can be taken with or without food. The key focus should be on ensuring that the medication is taken consistently and as prescribed rather than timing it around meals.

Summary:

The most important instruction for parents is to avoid crushing the tablet as it can alter the medication's effectiveness. Other instructions regarding food and sunlight are not as critical in this case.