The Role of N-acetyl-l-cysteine (NAC) as an Adjuvant to Opioid Treatment in Patients With Chronic Neuropathic Pain

Study Overview
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Brief Summary
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This study will test whether treatment with N-acetyl-L-cysteine (NAC) is safe and decreases pain in patients with chronic neuropathic pain. The investigators hypothesize that NAC will be a useful adjunct to opioid treatment in chronic neuropathic pain.

Detailed Description
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This is an open-label study to evaluate the safety and efficacy of N-acetyl-L-cysteine in patients with Chronic neuropathic pain.

Official Title
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The Role of N-acetyl-l-cysteine (NAC) as an Adjuvant to Opioid Treatment in Patients With Chronic Neuropathic Pain

Conditions
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Neuropathic Pain

Intervention / Treatment
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* Drug: N-acetyl-l-cysteine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18-65 years old non-cancer neuropathic pain stable dose of opioids for pain using breakthrough pain meds still with persistent pain per VAS Exclusion Criteria: pregnant or nursing serious medical or psychiatric illness (including uncontrolled hypertension) active stomach ulcer, history or seizures or asthma breakthrough pain meds other than opioids using illicit drugs

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: N-acetyl-L-cysteine<br>n-acetyl-l-cysteine 1200 mg BID x 4 weeks | Drug: N-acetyl-l-cysteine<br>* 1200 mg BID x 4 weeks<br>* Other names: NAC;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Opioid Use | The amount of opioid medication used was recorded. Then, it was converted to morphine equivalents (https://www.cms.gov/Medicare/Prescription-Drug-Coverage/PrescriptionDrugCovContra/Downloads/Opioid-Morphine-EQ-Conversion-Factors-March-2015.pdf). Opioid use was measured over a 2-week baseline period. Then, the average opioid medication use/week was calculated. This was compared to the average opioid medication use/week after 4 weeks of NAC. | Baseline, 4 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pain | Pain intensity will be measured by using the 100-point Visual Analogue Scale, a 100-mm horizontal line with anchors of no pain at all (at 0) and worst pain imaginable (at 100mm) on which patients' pain intensities are measured. | Baseline, 4 weeks | 
| Mood | Mood will be assessed by using the Patient Health Questionnaire (PHQ-9), a validated 9-question assessment of depression with total scores ranging from 0-27. Higher score = worse depression. | Baseline, 4 weeks | 
| Stress | Stress will be measured by the Perceived Stress Scale ((PSS), a 10-item instrument for measuring the perception of stress, with total scores ranging from 0-40. Higher scores = higher perceived stress | Baseline, 4 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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uncontrolled, neuropathic pain