Positives

• One individual found that incorporating branched-chain amino acids into their regimen improved their post-exertional malaise (PEM), noting that amino acids are often overused during PEM episodes Reddit.
  
  
• One individual highlighted BCAAs as part of a list of supplements that can reduce or prevent PEM, suggesting potential benefits for those with ME/CFS Phoenix Rising.
  
  

Negatives

• Drugs.com lists side effects of BCAAs as nausea, vomiting, headaches, and fatigue, especially when taken on an empty stomach or in high doses; some patients describe a strong bitter aftertaste that lingers for hours. Drugs.com.
• WebMD warns that BCAAs may decrease levodopa absorption and lower its effectiveness in Parkinson's patients, and they can also potentiate the blood-sugar-lowering effect of insulin or oral antidiabetic drugs, raising hypoglycemia risk. WebMD.
• A PMC review of amino acid supplement safety reports that BCAAs can interact with diabetes medications, blood pressure drugs, and liver disease therapies, and adverse GI effects are reported even at standard intake. PMC.

Hurdles & Side Effects

• One person dealing with moderate ME/CFS reported that managing fluid intake and electrolyte balance, potentially related to BCAA use, was challenging and impacted their sleep Reddit.