Age

18–75

Sex

ALL

Healthy volunteers

Not accepted

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

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

NAC-REPAIR for Post-surgical Pain