What is the next best approach for an 86-year-old patient with lower extremity (LE) pain, taking furosemide (Lasix) 20 mg, meloxicam (Mobic) 7.5 mg, and spironolactone (Aldactone) 25 mg, presenting with mild ankle edema, discoloration on the anterior shins, peripheral vascular disease, and neuropathy, with impaired renal function, as evidenced by an estimated glomerular filtration rate (eGFR) of 46?

From the Guidelines

For this 86-year-old patient with lower extremity pain, mild ankle edema, shin discoloration, peripheral vascular disease, and neuropathy, the next best approach would be to maintain the current furosemide (Lasix) dose and spironolactone dose, and divide the gabapentin dose to include daytime administration to improve neuropathic pain control throughout the day. I recommend 300 mg of gabapentin three times daily (morning, afternoon, and night) rather than just at bedtime. This approach provides better round-the-clock pain management without increasing the risk of adverse effects from diuretics, particularly given the patient's age and reduced renal function (eGFR 46) 1. The patient's current medication regimen, including furosemide and spironolactone, should be monitored closely for signs of hyperkalemia, hypokalemia, and changes in renal function, as these medications can have adverse effects in older adults with reduced kidney function 1. Additionally, gabapentin has been shown to be effective in treating neuropathic pain in older adults, with a recommended dose of 300-3600 mg/day 1. Regular monitoring of electrolytes, kidney function, and blood pressure is essential with this regimen. The combination of optimized gabapentin dosing and careful monitoring of the patient's medication regimen should improve both the edema and neuropathic pain symptoms, while minimizing the risk of adverse effects. It is also important to consider the patient's overall health status, including their peripheral vascular disease and neuropathy, when making treatment decisions, and to prioritize their quality of life and functional status 1.

From the FDA Drug Label

5.2 Hypotension and Worsening Renal Function

Excessive diuresis may cause symptomatic dehydration, hypotension and worsening renal function, particularly in salt-depleted patients or those taking angiotensin converting enzyme inhibitors and angiotensin II receptor blockers.

5 WARNINGS AND PRECAUTIONS Warnings and precautions 5.1 Hyperkalemia

Spironolactone can cause hyperkalemia. This risk is increased by impaired renal function or concomitant potassium supplementation, potassium-containing salt substitutes or drugs that increase potassium, such as angiotensin converting enzyme inhibitors and angiotensin receptor blockers [see Drug Interactions (7. 1)] .

Furosemide did not induce sister chromatid exchange in human cells in vitro, but other studies on chromosomal aberrations in human cells in vitro gave conflicting results. Geriatric Use Controlled clinical studies of Furosemide tablets did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects Other reported clinical experience has not identified differences in responses between the elderly and younger patients.

The patient has mild edema, peripheral vascular disease, and neuropathy. Given the patient's eGFR of 46, which indicates impaired renal function, and the fact that they are taking spironolactone and furosemide, the risk of worsening renal function and hyperkalemia should be considered.

• The patient's renal function should be monitored periodically.
• Electrolyte and metabolic abnormalities should also be monitored.
• Given the patient's age and renal function, dose selection for furosemide should be cautious.
• The patient's volume status should be monitored to avoid symptomatic dehydration and hypotension.
• No conclusion can be drawn about adjusting spironolactone or lasix without more information about the patient's potassium levels and renal function.
• The use of gabapentin during the day may be considered for the patient's neuropathy, but this is not directly related to the management of edema or renal function 2 3.

From the Research

Patient Assessment

• The patient is an 86-year-old with lower extremity (LE) pain, taking furosemide 20 mg, meloxicam 7.5 mg, and spironolactone 25 mg, and experiencing ankle edema and discoloration to the anterior shins.
• The patient has peripheral vascular disease and neuropathy, for which they take gabapentin at night.
• The patient's eGFR is 46, indicating impaired renal function.

Medication Management

• The patient's edema is mild, and it may not be necessary to adjust the spironolactone or furosemide doses 4.
• However, the patient's renal function should be considered when adjusting diuretic doses, as furosemide pharmacokinetics can be altered in patients with chronic renal failure 5.
• The patient's gabapentin dose could be increased to be taken during the day, but this should be done with caution due to the potential risk of peripheral edema and acute heart failure associated with gabapentinoids 6.

Treatment Approach

• The optimal dose of furosemide and spironolactone for elderly patients with diastolic heart failure is 20 mg/day and 40 mg/day, respectively 7.
• A systematic approach to reviewing the patient's medication regimen can help identify potential problems and simplify the regimen 8.
• The patient's medication regimen should be regularly reviewed to ensure that the medications are not creating more problems than they solve, and to identify any potential drug-drug or drug-disease interactions 8.

Potential Adjustments

• Consider increasing the spironolactone dose to 40 mg/day, as this has been shown to be effective in elderly patients with diastolic heart failure 7.
• Monitor the patient's renal function and adjust the furosemide dose as needed to avoid worsening renal function 5.
• Consider the potential risks and benefits of increasing the gabapentin dose, and monitor the patient for signs of peripheral edema and acute heart failure 6.