NAC-REPAIR for Post-surgical Pain

University of Arizona

Status and phase: Not yet enrolling; Phase 2

Conditions: Tarsal Tunnel Syndrome; De Quervain Syndrome; Guyon's Canal; Peroneal Nerve Entrapment; Dupuytren Contracture; Plantar Fasciopathy; Trigger Finger Disorder; Morton Neuroma; Carpal Tunnel Surgery

Treatments: Drug: NAC; Drug: NAC 0mg/day (Placebo)

Study type: Interventional

Funder types: Other

Identifiers

NCT07227649

STUDY00007009

Details and patient eligibility

About

This pilot asks whether peri-operative N-acetylcysteine (NAC) improves recovery after common outpatient hand/foot-ankle surgery-specifically, does NAC reduce pain and opioid use and enhance function by modulating redox-inflammatory pathways? Primary objectives are to establish feasibility (accrual, adherence, follow-up), estimate NAC vs placebo effects on pain, function, and opioid consumption, and characterize inflammatory signatures that may predict response.

Methods: a single-site, double-blind, 1:1 randomized trial (N≈80) comparing NAC 1,200 mg twice daily for 14 days (starting pre-op) vs matching placebo; daily e-diaries for POD0-14; standardized outcomes (PROMIS Pain Interference; QuickDASH or FAAM; PGIC; opioid MME); and small blood draws pre-surgery and at two follow-up visits for cytokine profiling.

Enrollment: 80 estimated patients

Sex: All

Ages: 18 to 75 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Elective outpatient hand/upper-extremity or foot/ankle surgery (single site; same-day discharge)
• Baseline visit feasible ≤14 days pre-op
• Can complete surveys/blood draw
• Provides informed consent
• Willing to follow dosing schedule and avoid restricted supplements/meds

Exclusion criteria

• Allergy to NAC/capsule components □ NAC or high-dose antioxidants in past 14 days (unwilling to stop)
• Chronic daily opioids ≥3 months or OUD/maintenance therapy □ Pregnant/breastfeeding or no contraception as applicable
• Daily nitrates (nitroglycerin/isosorbide) □ Planned >24h admission, multistage/trauma case □ Other interventional study within 30 days
• Unable to swallow capsules / malabsorption surgery affecting oral meds

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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80 participants in 2 patient groups, including a placebo group

N-Acetylcysteine (NAC)

Experimental group

Description:

Intervention: Oral N-acetylcysteine capsules, 600 mg twice daily. Timing/Duration: Begin the evening before surgery (≤24 h pre-op) and continue through Post-op Day 14 (total 15 days; bottle overfilled to cover missed doses). Administration: Self-administered at home; counseling at baseline dispense; pill diary + pill counts. Concomitant care: All peri-operative care per standard of care (SoC), including multimodal analgesia; no high-dose antioxidant supplements; nitrates excluded. Objective: Test whether peri-operative NAC improves early pain, function, and recovery via redox-immune modulation.

Treatment:

Drug: NAC

Placebo

Placebo Comparator group

Description:

Intervention: Matched inert capsules (e.g., microcrystalline cellulose), identical in size/appearance/labeling to NAC. Timing/Duration: 600 mg-equivalent capsule count, twice daily, evening before surgery through Post-op Day 14. Administration: Same counseling, diary, and adherence checks as NAC arm. Concomitant care: Identical SoC allowances/restrictions as NAC arm.

Treatment:

Drug: NAC 0mg/day (Placebo)