What is the recommended use of branched-chain amino acids (BCAAs) as a supplement for an adolescent or young adult patient who has experienced a concussion?

Branched-Chain Amino Acids for Concussion: Current Evidence and Recommendations

Based on the available evidence, BCAAs show preliminary promise for reducing concussion symptoms and accelerating return to physical activity in adolescents and young adults, but cannot yet be routinely recommended as standard treatment due to limited human data. 1

Evidence for BCAA Use in Concussion

Human Trial Results

The only human trial of BCAAs in concussed adolescents and young adults (ages 11-34) demonstrated:

• No improvement in the primary outcome (processing speed on neurocognitive testing) 1
• Significant dose-response reduction in total symptom scores (4.4-point decrease per 500g consumed on 0-54 scale, p=0.0036) 1
• Accelerated return to physical activity (0.503-point increase per 500g consumed on 0-5 scale, p=0.005) 1
• Good safety profile with only 2 mild gastrointestinal adverse events in the highest dose groups (45-54g daily) 1

Dosing Protocol from Human Trial

The study tested five arms over 21 days: 1

• Placebo
• 15g BCAA daily
• 30g BCAA daily
• 45g BCAA daily
• 54g BCAA daily

Higher total cumulative doses showed better outcomes, suggesting that if used, doses in the 45-54g daily range may be most effective. 1

Critical Limitations

Why BCAAs Cannot Be Routinely Recommended

• The FDA has not approved any supplement for concussion treatment 2
• Only one small human trial exists (38 analyzable participants), limited by slow enrollment, small sample size, and missing data 1
• Animal studies may not translate to sports-related concussion, as most animal research involves severe TBI rather than mild concussion 2
• No evidence exists for BCAAs in the established concussion treatment guidelines from the American Academy of Pediatrics, PM&R consensus statement, or other major organizations 3, 4

Current Standard of Care Takes Priority

Evidence-Based Interventions That Should Come First

Aerobic exercise is the only intervention with strong evidence for adolescents with acute concussion, supported by high-quality RCTs with low-to-moderate risk of bias. 3, 4 This should be the primary therapeutic intervention after the initial 24-48 hour rest period. 4, 5

The established treatment protocol includes: 3, 4

• Initial 24-48 hours: Complete physical and cognitive rest
• After 48 hours: Begin supervised, sub-threshold aerobic exercise
• Progressive return protocol: Light aerobic activity → sport-specific exercise → non-contact drills → full-contact practice → return to play
• Minimum 24 hours between each step, advancing only if symptom-free

If Considering BCAA Supplementation

Practical Approach

If you choose to use BCAAs as an adjunct (not replacement) to standard care, based on the single human trial: 1

Dosing: 45-54g daily divided into multiple doses Duration: Continue for at least 21 days or until symptom resolution Formulation: The trial used oral BCAA powder supplements Monitoring: Track total symptom scores and physical activity levels

Safety Considerations

• Generally well-tolerated in the adolescent/young adult population 1
• Mild gastrointestinal effects possible at higher doses (45-54g daily) 1
• No serious adverse events reported in the concussion trial 1

Important Caveats

• BCAAs alone are insufficient for muscle protein synthesis compared to complete protein sources containing all indispensable amino acids 6
• Do not delay or replace evidence-based exercise therapy with BCAA supplementation 3, 4
• Inform patients this is experimental with limited human evidence 1, 2

Clinical Decision Algorithm

1. Implement standard concussion management first: 24-48 hour rest followed by graded aerobic exercise 4, 5
2. If symptoms persist beyond 7-10 days or patient/family requests additional interventions, consider discussing BCAAs as experimental adjunct 1
3. If using BCAAs: Start 45-54g daily, monitor symptom scores and activity tolerance 1
4. Continue standard multimodal management including vestibular rehabilitation, cognitive rehabilitation, or other therapies as clinically indicated 4, 7

Bottom Line

Exercise therapy remains the cornerstone of concussion treatment in adolescents with the strongest evidence base. 3, 4 BCAAs represent an investigational option that showed preliminary benefit in one small trial for symptom reduction and return to activity, but lack sufficient evidence for routine recommendation. 1 If used, they should complement—not replace—established treatment protocols, with doses of 45-54g daily appearing most effective based on available data. 1