From the Guidelines
For treating shingles pain in dialysis patients, a carefully adjusted medication approach is recommended, prioritizing gabapentin or pregabalin for neuropathic pain, with dose adjustments for kidney failure, as seen in a case study from 1. When managing shingles pain in patients undergoing dialysis, it's crucial to consider the altered drug clearance and potential for toxicity. Key considerations include:
- Starting with gabapentin (100-300mg after each dialysis session) or pregabentin (25-75mg daily), which are preferred for neuropathic pain but require dose reduction in kidney failure, as noted in the context of medication reconciliation for patients on dialysis 1.
- Using acetaminophen (up to 3000mg daily) for breakthrough pain, as it is safer than NSAIDs, which should be avoided in dialysis patients due to the risk of further kidney damage.
- Applying topical lidocaine patches (5%) to painful areas for 12 hours daily for localized relief without systemic effects.
- Considering tramadol (50-100mg after dialysis) or low-dose opioids for severe pain, with close monitoring due to the risk of accumulation and adverse effects between dialysis sessions.
- Initiating antiviral medications like acyclovir within 72 hours of rash appearance, at reduced doses (e.g., 200mg daily), to minimize the risk of toxicity in the context of impaired renal function, as illustrated by the case of an 89-year-old man receiving peritoneal dialysis and diagnosed with herpes zoster 1. Given the complexities of managing pain in dialysis patients, consultation with both a nephrologist and a pain specialist is essential to balance effective pain control with the need to avoid medication toxicity, especially considering the impact of dialysis on drug clearance 1.
From the FDA Drug Label
Table 1. VALTREX Dosage Recommendations for Adults with Renal Impairment Indications Normal Dosage Regimen (Creatinine Clearance ≥50 mL/min) Creatinine Clearance (mL/min) 30-49 10-29 <10 Cold sores (Herpes Labialis) Do not exceed 1 day of treatment Herpes Zoster 1 gram 3 times daily for 7 days 1 gram twice daily for 7 days 500 mg twice daily for 7 days 500 mg once daily for 7 days
For the treatment of shingles pain in patients undergoing dialysis, the recommended dosage of valacyclovir is 500 mg once daily for 7 days 2.
- Key points:
- The dosage of valacyclovir should be adjusted according to the patient's renal function.
- Patients with renal impairment, including those on dialysis, require a reduced dosage of valacyclovir.
- The recommended dosage for patients with a creatinine clearance of less than 10 mL/min is 500 mg once daily for 7 days.
- Important consideration: Patients with renal impairment are at a higher risk of developing adverse reactions, including renal failure, and should be closely monitored while receiving valacyclovir therapy 2.
From the Research
Shingles Pain Treatment and Dialysis
- Shingles, also known as herpes zoster, can occur in anyone with a history of chickenpox, but it is more prevalent and severe in older patients 3.
- The pain associated with shingles can persist for several months or even years, and is known as post-herpetic neuralgia (PHN) 3, 4, 5, 6.
- Antiviral medications such as aciclovir, famciclovir, and valaciclovir can be used to treat shingles, and may help reduce the duration of PHN 3, 4, 5, 6.
- For patients undergoing dialysis, the risk of developing shingles is increased compared to the general population 7.
- The incidence rate of shingles was found to be significantly higher in patients undergoing hemodialysis compared to a control cohort, with an adjusted hazard ratio of 1.98 (95% CI, 1.72-2.27) 7.
Treatment Options for Shingles Pain
- Topical lidocaine and capsaicin can be effective in treating PHN 4, 5, 6.
- Systemic agents such as gabapentin, pregabalin, and tricyclic antidepressants can also be used to treat PHN 4, 5, 6.
- Opioid analgesics such as tramadol, morphine, and oxycodone may be considered for patients with severe pain 4, 5, 6.
- Early initiation of gabapentin or amitriptyline after the onset of shingles may help reduce the risk of developing PHN 4.