Question 1

A nurse is caring for a patient who takes an ACE inhibitor and an ARB medication who will begin taking TMP/SMZ to treat a urinary tract infection. Which serum electrolyte will the nurse expect to monitor closely?

A) Calcium
B) Chloride
C) Potassium
D) Sodium

Potassium

Accepted Answer

Trimethoprim suppresses renal excretion of potassium, increasing the risk of hyperkalemia. Patients at greatest risk are those taking high doses of trimethoprim and those taking other drugs that elevate potassium, including ACE inhibitors and ARB medications. Trimethoprim does not affect other serum electrolytes.

Question 2

A patient will be discharged from the hospital with a prescription for TMP/SMZ [Bactrim]. When providing teaching for this patient, the nurse will tell the patient that it will be important to:&#10;A) drink 8 to 10 glasses of water each day.&#10;B) eat foods that are high in potassium.&#10;C) take the medication with food.&#10;D) take folic acid supplements.

Accepted Answer

TMP/SMZ can injure the kidneys, because it causes deposition of sulfonamide crystals in the kidneys. Patients should be advised to drink 8 to 10 glasses of water a day to maintain a urine flow of 1200 mL in adults. Trimethoprim can cause hyperkalemia, so consuming extra potassium is unnecessary. The medication should be taken on an empty stomach. It is not necessary to consume extra folic acid, because mammalian cells use dietary folate and do not have to synthesize it; it is the process of folic acid synthesis that is altered by sulfonamides.

Question 3

A nurse is discussing microbial resistance among sulfonamides and trimethoprim with a nursing student. Which statement by the student indicates a need for further teaching?&#10;A) &#34;Bacterial resistance to trimethoprim is relatively uncommon.&#34;&#10;B) &#34;Resistance among gonococci, streptococci, and meningococci to sulfonamides is high.&#34;&#10;C) &#34;Resistance to both agents can occur by spontaneous mutation of organisms.&#34;&#10;D) &#34;Resistance to sulfonamides is less than resistance to trimethoprim.&#34;

Accepted Answer

There is less microbial resistance to trimethoprim than there is to sulfonamides. Bacterial resistance to trimethoprim is relatively uncommon. Gonococcal, streptococcal, and meningococcal resistance to sulfonamides is especially high. For both agents, resistance can develop by spontaneous mutation.

Question 4

A patient who is taking immunosuppressant medications develops a urinary tract infection. The causative organism is sensitive to sulfonamides and to another, more expensive antibiotic. The prescriber orders the more expensive antibiotic. The nursing student assigned to this patient asks the nurse why the more expensive antibiotic is being used. Which response by the nurse is correct?

A) "Immunosuppressed patients are folate deficient."
B) "Patients who are immunosuppressed are more likely to develop resistance."
C) "Sulfonamides are bacteriostatic and depend on host immunity to work."
D) "Sulfonamides intensify the effects of immunosuppression."

Accepted Answer

Sulfonamides are usually bacteriostatic and require intact host defenses for complete elimination of infection. Immunosuppressed patients are not necessarily folate deficient. There is no increased likelihood of developing bacterial resistance in immunosuppressed patients. Sulfonamides do not affect immunosuppression.

Question 5

A patient with type 2 diabetes mellitus takes glipizide. The patient develops a urinary tract infection, and the prescriber orders TMP/SMZ. What will the nurse tell the patient?&#10;A) Patients with diabetes have an increased risk of an allergic reaction.&#10;B) Patients taking TMP/SMZ may need increased doses of glipizide.&#10;C) The patient should check the blood glucose level more often while taking TMP/SMZ.&#10;D) The patient should stop taking the glipizide while taking the TMP/SMZ.

Accepted Answer

Sulfonamides can intensify the effects of some drugs, including glipizide, which is a sulfonylurea-type hypoglycemic medication. These drugs may require a reduction in dose to prevent toxicity. Patients should monitor their blood glucose more closely. There is no increase in allergic reactions to TMP/SMZ in patients who are diabetic. Patients taking TMP/SMZ may need reduced doses of glipizide but should not stop taking the drug.

Question 6

A pregnant patient is treated with trimethoprim/sulfamethoxazole (TMP/SMZ) [Bactrim] for a urinary tract infection at 32 weeks' gestation. A week later, the woman delivers her infant prematurely. The nurse will expect to monitor the infant for:

A) birth defects.
B) hypoglycemia.
C) rash.
D) kernicterus.

Accepted Answer

Kernicterus is a disorder in newborns caused by deposition of bilirubin in the brain. Sulfonamides promote kernicterus by displacing bilirubin from plasma proteins. Sulfonamides should not be given to infants under 2 months of age or to pregnant women after 32 weeks' gestation. Sulfonamides do not cause birth defects or hypoglycemia. Serious rashes may occur but are not the primary concern in the newborn.

Question 7

A nurse teaches a patient about sulfonamides. Which statement by the patient indicates a need for further teaching?&#10;A) &#34;I need to drink extra fluids while taking this medication.&#34;&#10;B) &#34;I need to use sunscreen when taking this drug.&#34;&#10;C) &#34;I should call my provider if I develop a rash while taking this drug.&#34;&#10;D) &#34;I should stop taking this drug when my symptoms are gone.&#34;

Accepted Answer

Patients should always be advised to complete the prescribed course of the antibiotic even when symptoms subside. Patients should also understand the need to drink 8 to 10 glasses of water a day, to use sunscreen, and to notify the provider if they develop a rash.

Question 8

A patient with bronchitis is taking TMP/SMZ, 160/800 mg orally, twice daily. Before administering the third dose, the nurse notes that the patient has a widespread rash, a temperature of 103°F, and a heart rate of 100 beats/min. The patient looks ill and reports not feeling well. What will the nurse do?

A) Administer the dose and request an order for an antipyretic medication.
B) Withhold the dose and request an order for an antihistamine to treat the rash.
C) Withhold the dose and notify the provider of the symptoms.
D) Request an order for intravenous TMP/SMZ, because the patient is getting worse.

Accepted Answer

The most severe hypersensitivity reaction with TMP/SMZ is Stevens-Johnson syndrome, which manifests with fever, malaise, and rash. The drug should be discontinued immediately if a rash occurs. Requesting an antipyretic while giving the drug is incorrect. Giving antihistamines is not indicated. Giving TMP/SMZ intravenously would make the reaction worse.

Question 9

A patient with second-degree burns is treated with silver sulfadiazine [Silvadene]. A nursing student asks the nurse about the differences between silver sulfadiazine and mafenide [Sulfamylon], because the two are similar products, and both contain sulfonamides. What does the nurse tell the student about silver sulfadiazine?

A) It causes increased pain when the medication is applied.
B) It has a broader spectrum of antimicrobial sensitivity.
C) It has antibacterial effects related to release of free silver.
D) It suppresses renal excretion of acid, causing acidosis.

Accepted Answer

Silver sulfadiazine has antibacterial effects primarily related to the release of free silver and not to the sulfonamide portion of the molecule. Unlike mafenide, silver sulfadiazine reduces pain when applied. Silver sulfadiazine and mafenide have similar antibacterial effects. Because silver sulfadiazine does not suppress renal excretion of acid, it has fewer systemic effects.

Question 10

A nurse is obtaining a drug history from a patient about to receive sulfadiazine. The nurse learns that the patient takes warfarin, glipizide, and a thiazide diuretic. Based on this assessment, the nurse will expect the provider to:

A) change the antibiotic to TMP/SMZ.
B) increase the dose of the glipizide.
C) monitor the patient's electrolytes closely.
D) monitor the patient's coagulation levels.

Accepted Answer

Sulfonamides interact with several drugs and through metabolism-related interactions can intensify the effects of warfarin. Patients taking both should be monitored closely for bleeding tendencies. Changing to the combination product will not help, because sulfonamides are still present. Sulfonamides intensify glipizide levels, so this drug may actually need to be reduced. Trimethoprim, not sulfonamides, raises potassium levels.

Question 11

A patient with a urinary tract infection is given a prescription for TMP/SMZ. When reviewing the drug with the patient, the nurse learns that the patient has type 1 diabetes mellitus and consumes alcohol heavily. What will the nurse do?

A) Contact the provider to request a different antibiotic for this patient.
B) Obtain frequent blood glucose determinations while giving TMP/SMZ.
C) Suggest that the patient takes a potassium supplement while taking TMP/SMZ.
D) Tell the patient to avoid excessive fluid intake while taking TMP/SMZ.

Accepted Answer

The answer of A patient with a urinary tract infection...

Question 12

A nurse is caring for an African American patient who has been admitted to the unit for long-term antibiotic therapy with sulfonamides. The patient develops fever, pallor, and jaundice. The nurse would be correct to suspect that the patient has developed:

A) Stevens-Johnson syndrome.
B) kernicterus.
C) hepatotoxicity.
D) hemolytic anemia.

Accepted Answer

The answer of A nurse is caring for an African...

Deck 88: Sulfonamides and Trimethoprim