Overview
Safety in plain terms
Generally tolerable; herpes reactivation and GI distress appear in subsets at higher doses.
Tolerability
Commonly reported effects
- Bloating and diarrhea at high oral doses
Higher-risk contexts
Who should pause or get medical guidance first
- Recent MI or unstable angina without cardiology clearance
- Active herpes flares sensitive to arginine in some reports
Polypharmacy
Interactions & cautions
- PDE5 inhibitors and blood pressure meds
- IV arginine is medical only
Practical
Dose context (not a prescription)
Post-MI stacking and unstable angina are not DIY supplement territory.
Our editorial safety score is 70/100 - methodology and limitations are on the full hub page.
Verdict context
Studies conflict or are small; some plausible benefits, but the signal is too noisy for strong claims.
Same ingredient, other questions
Focused pages for common searches about L-arginine. Each uses the same underlying evidence file with a different lens.
Explore further
A few hand-picked entry points around L-arginine: categories, answers to narrow questions, and comparisons.
Focused questions
Related ingredients
Ingredients we group near L-arginine in our model - not interchangeable, but often read together.
- Creatine90/100Strong support
One of the most studied ergogenic aids; strongly supports high-intensity performance and lean mass when training is consistent.
- Whey protein84/100Strong support
A complete protein source convenient for hitting protein targets; evidence is mostly about adequate protein intake, not magic anabolism.
- Beta-alanine83/100Strong support
Buffers hydrogen ions during high-intensity efforts; best evidence for short repeated sprints and 1-4 minute efforts.
Alternatives
Swaps people discuss alongside L-arginine - still judge each ingredient on its own evidence.