Examkin

Soru

Zorluk: OrtaPharmacologic Interventions

A 72-year-old woman is evaluated in the ambulatory care clinic for a routine follow-up. She has a history of type 2 diabetes mellitus, osteoarthritis, hypertension, and recurrent uncomplicated urinary tract infections. Her current medications include metformin 1000 mg twice daily, sitagliptin 100 mg daily, meloxicam 15 mg daily, nitrofurantoin 100 mg daily, and amlodipine 10 mg daily. The patient reports feeling well overall, though she mentions mild fatigue over the past few weeks. Blood pressure is 132/82 mmHg, and pulse is 76/min. Physical examination is unremarkable, with no peripheral edema.

Laboratory results from today are compared to those from six months ago:

Laboratory TestCurrentSix Months Ago
Blood urea nitrogen42 mg/dL18 mg/dL
Serum creatinine2.6 mg/dL1.1 mg/dL
eGFR19 mL/min/1.73 m²55 mL/min/1.73 m²
Serum potassium4.8 mEq/L4.2 mEq/L

Based on the patient's current laboratory results, which of the following medications must be entirely DISCONTINUED? (Select all that apply)

  1. MetforminCevap
  2. MeloxicamCevap
  3. NitrofurantoinCevap
  4. D
    Sitagliptin
  5. E
    Amlodipine

Cevap

Metformin, Meloxicam, and Nitrofurantoin must be discontinued.
This patient has developed severe renal impairment (eGFR < 30 mL/min/1.73 m²). In this setting, metformin must be discontinued due to a significantly elevated risk of life-threatening lactic acidosis. Meloxicam, an NSAID, must be stopped because it inhibits prostaglandins that are actively dilating the afferent arteriole to maintain glomerular filtration, further worsening renal function. Nitrofurantoin must also be discontinued because it is essentially cleared by glomerular filtration; at an eGFR < 30 mL/min/1.73 m², it fails to reach therapeutic levels in the urinary tract to prevent UTIs and instead accumulates systemically, leading to pulmonary toxicity and peripheral neuropathy.

Adım Adım Çözüm

1
Analyze the patient's updated laboratory findings.
The patient's eGFR has rapidly declined from 55 to 19 mL/min/1.73 m², indicating new-onset Stage 4 chronic kidney disease (CKD) or acute-on-chronic kidney injury.
Renal function directly determines the safety, efficacy, and necessary dosing adjustments for many pharmacologic agents.
2
Evaluate the current medication list against the new eGFR of 19 mL/min/1.73 m².
Identify which medications are absolutely contraindicated, which need dose adjustments, and which are safe to continue.
Continuing contraindicated medications in advanced CKD can lead to severe systemic toxicity or worsen renal failure.
3
Select the medications that require complete discontinuation.
Metformin (lactic acidosis risk), meloxicam (worsens renal perfusion), and nitrofurantoin (lack of efficacy and high toxicity risk) must be stopped. Sitagliptin only requires a dose reduction, and amlodipine requires no changes.
Differentiating between drugs requiring dose adjustments and those requiring absolute discontinuation is critical for safe medication reconciliation.

Anahtar Kavram

Medication reconciliation and identification of absolute pharmacologic contraindications in the setting of severely impaired renal function (eGFR < 30 mL/min/1.73 m²).
Bu soruyu puanla

Konular

Pharmacologic Interventions

Bu konudan daha fazla soru