Liver extract-folic acid-cyanocobalamin vs placebo for chronic fatigue syndrome

Arch Intern Med. 1989 Nov;149(11):2501-3.


Chronic fatigue syndrome is a recently defined entity for which clinical criteria were proposed by the Centers for Disease Control, Atlanta, Ga. A frequently advocated treatment in Southern California is an injectable solution of bovine liver extract containing folic acid and cyanocobalamin (LEFAC). We conducted a double-blind, placebo-controlled, crossover trial of intramuscular LEFAC in 15 patients who met the Centers for Disease Control criteria for chronic fatigue syndrome. Although patients responded to placebo and LEFAC by several criteria of functional status, no significant difference was apparent between response to placebo and that to LEFAC. The placebo response appeared to be strong.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Double-Blind Method
  • Drug Combinations
  • Fatigue Syndrome, Chronic / drug therapy*
  • Female
  • Folic Acid / administration & dosage*
  • Folic Acid / therapeutic use
  • Humans
  • Liver Extracts / administration & dosage*
  • Liver Extracts / therapeutic use
  • Male
  • Middle Aged
  • Randomized Controlled Trials as Topic
  • Vitamin B 12 / administration & dosage*
  • Vitamin B 12 / therapeutic use


  • Drug Combinations
  • Liver Extracts
  • Folic Acid
  • Vitamin B 12