Research synthesisLow evidenceModerate effect3 studies · 2 beneficial · 1 neutral · 0 harmful
Across 3 studies, 2 reported beneficial moderate-sized effects of L-arginine on reducing pain, while 1 found no significant benefit. Evidence primarily comes from clinical populations with sickle cell disease experiencing vaso-occlusive crises or patients with radiation-induced oral mucositis, with doses ranging from 100 mg/kg/dose three times daily to 5 g daily. The median study duration was 49 days (based on 1 study), but effects were observed within 1-7 weeks.
- Effective dose range: 100 mg/kg/dose three times daily or 5 g daily
- Studied populations: children with sickle cell disease experiencing vaso-occlusive pain episodes; head and neck cancer patients with radiation-induced oral mucositis
Caveats: Evidence base is small (only 3 studies) — conclusions should be considered preliminary. One meta-analysis with the largest sample size (n=830) found no statistically significant benefit, contrasting with two smaller RCTs showing moderate beneficial effects, suggesting possible publication bias or that effects may not generalize to all clinical populations.
Generated Jul 12, 2026