Recommended Treatment with Bactrim DS for Nursing Home Patients with Culture-Sensitive Infections
For nursing home patients with culture-sensitive infections, Trimethoprim-Sulfamethoxazole (TMP-SMZ) should be administered at a dose of trimethoprim 160 mg/sulfamethoxazole 800 mg (one double-strength tablet) orally twice daily for 14 days, with careful monitoring of renal function and potential drug interactions.
Dosing Considerations for Nursing Home Patients
The appropriate dosing of Bactrim DS (TMP-SMZ) for nursing home patients requires special consideration of several factors:
Standard Dosing Regimen
- For adults with normal renal function: One double-strength tablet (trimethoprim 160 mg/sulfamethoxazole 800 mg) twice daily 1
- Duration of therapy: 14 days for most infections 1
Renal Adjustment Considerations
- Nursing home patients often have decreased renal function
- Dosage adjustment is required when creatinine clearance is less than 30 mL/min 2, 3
- For patients with impaired renal function, consider:
- Monitoring serum creatinine and BUN before and during therapy
- Reducing dose or extending dosing interval based on creatinine clearance
Administration Guidelines
- TMP-SMZ should be administered by nursing home staff who directly observe the patient swallow the medication 1
- Maintain adequate fluid intake to prevent crystalluria 2
- Monitor for signs of drug toxicity with each dose 1
Monitoring During Treatment
Laboratory Monitoring
- Complete blood counts should be performed frequently 2
- Renal function tests (BUN, creatinine) should be monitored before and during therapy 2, 4
- Monitor serum potassium, especially in patients with underlying disorders of potassium metabolism or renal insufficiency 2
Clinical Monitoring
- Watch for signs of adverse reactions, particularly:
- Skin rash (may indicate need to discontinue therapy)
- Fever
- Gastrointestinal disturbances
- Signs of blood dyscrasias (unusual bleeding, bruising)
Special Considerations for Nursing Home Patients
Drug Interactions
- Use with caution in patients receiving:
Contraindications and Cautions
- Contraindicated in patients with known hypersensitivity to sulfonamides or trimethoprim 2
- Use with caution in patients with:
- Impaired renal or hepatic function
- Possible folate deficiency (common in elderly)
- Glucose-6-phosphate dehydrogenase deficiency
- History of severe allergies or bronchial asthma 2
Potential Adverse Effects
Common Adverse Effects
- Gastrointestinal disturbances
- Skin rash
- Elevated liver enzymes
Serious Adverse Effects
- Acute kidney injury (occurs in up to 11.2% of patients treated for ≥6 days) 4
- Hyperkalemia (especially in elderly with renal impairment) 2
- Blood dyscrasias
- Stevens-Johnson syndrome (rare)
Clinical Pearls
- TMP-SMZ has a half-life of 8-11 hours for trimethoprim and 10-13 hours for sulfamethoxazole, allowing for twice-daily dosing 1
- The drug has a moderate phlebitis risk rating if administered intravenously 1
- For nursing home patients with suspected UTIs, TMP-SMZ is highly effective but should be used with caution due to the higher risk of adverse effects in elderly patients 1
- Acute kidney injury typically resolves promptly after discontinuation of therapy 4
Alternative Agents
If TMP-SMZ cannot be tolerated or is contraindicated, consider alternative agents based on culture sensitivity results and the specific infection being treated. For UTIs, consider nitrofurantoin if renal function is adequate, or a fluoroquinolone if appropriate 1.