From the Guidelines
The most effective next step for managing postherpetic neuralgia (PHN) in a patient with persistent pain after shingles treatment on the lower back is to initiate or optimize first-line medications, including gabapentinoids or tricyclic antidepressants, and consider combination therapy with medications having different mechanisms of action, as supported by recent guidelines and studies 1.
First-Line Medications
For patients with PHN, first-line medications include gabapentinoids (gabapentin or pregabalin) and tricyclic antidepressants (amitriptyline or nortriptyline) 1. Gabapentin can be started at 300mg daily and titrated up to 1800-3600mg daily in divided doses, while pregabalin can be initiated at 75mg twice daily and increased to 300-600mg daily. Tricyclic antidepressants like amitriptyline or nortriptyline can be started at 10-25mg at bedtime and gradually increased to 75-150mg daily as tolerated.
Topical Treatments
Topical treatments such as lidocaine 5% patches applied to the painful area for 12 hours daily or capsaicin 8% patches applied by healthcare providers for 30-60 minutes every 3 months can provide localized relief for PHN patients 1.
Combination Therapy
For patients with inadequate response to first-line medications, combination therapy using medications with different mechanisms of action is recommended 1. This approach can include combining gabapentinoids with tricyclic antidepressants or adding selective serotonin norepinephrine reuptake inhibitors (SNRIs) like duloxetine or venlafaxine.
Second-Line Options and Referral
Second-line options for PHN management include SNRIs (duloxetine 30-60mg daily or venlafaxine 75-225mg daily) or tramadol 50-100mg every 4-6 hours (maximum 400mg daily) 1. Severe, refractory cases may require referral to pain specialists for interventional procedures such as nerve blocks, spinal cord stimulation, or intrathecal therapy. Additionally, physical therapy and psychological approaches like cognitive behavioral therapy can complement pharmacological treatment.
Multimodal Approach
PHN pain management requires a multimodal approach because the condition involves complex mechanisms including nerve damage, central sensitization, and inflammatory processes following herpes zoster reactivation 1. This approach should be tailored to the individual patient's needs and may involve a combination of pharmacological, interventional, and non-pharmacological strategies.
From the FDA Drug Label
In adults with postherpetic neuralgia, gabapentin may be initiated on Day 1 as a single 300 mg dose, on Day 2 as 600 mg/day (300 mg two times a day), and on Day 3 as 900 mg/day (300 mg three times a day). The dose can subsequently be titrated up as needed for pain relief to a dose of 1800 mg/day (600 mg three times a day)
The next steps for managing postherpetic neuralgia (PHN) in a patient with persistent pain after shingles treatment on the lower back include:
- Initiating or adjusting gabapentin dosage: The patient may be started on gabapentin with a dose of 300 mg on Day 1,600 mg/day on Day 2, and 900 mg/day on Day 3, with subsequent titration up to 1800 mg/day as needed for pain relief 2.
- Monitoring for efficacy and side effects: The patient should be monitored for reduction in pain scores and for potential side effects such as suicidal thoughts, changes in behavior, allergic reactions, and breathing problems 2.
- Considering alternative or adjunctive treatments: If gabapentin is not effective or is not tolerated, other treatment options such as amitriptyline, capsaicin, or lidocaine may be considered.
- Close follow-up: The patient should be followed closely to assess the response to treatment and to adjust the treatment plan as needed.
From the Research
Next Steps for Managing Postherpetic Neuralgia (PHN)
- For patients with persistent pain after shingles treatment on the lower back, several treatment options can be considered, including antivirals, analgesics, and nerve blocks, as these can effectively shorten the course of shingles and may help to prevent PHN 3, 4.
- Pharmacological treatment of PHN may include a variety of medications such as alpha-2 delta ligands (gabapentin and pregabalin), other anticonvulsants (carbamazepine), tricyclic antidepressants (amitriptyline, nortriptyline, doxepin), topical analgesics (5% lidocaine patch, capsaicin) tramadol, or other opioids 5, 6.
- A series of thoracic transforaminal epidural steroid injections (TFESIs) can be considered an early and first-choice treatment for PHN, but several courses may be required to achieve adequate and prolonged symptom control 3.
- Nurses and patients can work together in partnership to achieve the best outcomes by using a combination of biomedical and self-care approaches, and realizing that more than one approach may be needed 7.
- Treatment should be tailored based on the response of individual patients, considering the considerable side effect profiles of commonly used oral medications, and a combination of both topical and systemic agents may be required for optimal outcomes 6.
Treatment Options
- Antivirals: acyclovir, famciclovir, valacyclovir 4
- Analgesics: gabapentin, pregabalin, amitriptyline, oxycodone/acetaminophen 3, 5
- Nerve blocks: thoracic transforaminal epidural steroid injections (TFESIs) 3
- Topical analgesics: 5% lidocaine patch, capsaicin 6
- Tricyclic antidepressants: amitriptyline, nortriptyline, doxepin 6
- Opioids: tramadol, other opioids 6
Considerations
- The chronic neuropathic pain of PHN can persist for months or years after the acute herpes zoster episode and can severely impact the overall quality of life 3.
- PHN can be highly debilitating and may require narcotics for adequate pain control 4.
- Treatment should be individualized and may require a combination of therapies to achieve optimal outcomes 7, 6.