L-tryptophan in the treatment of impaired respiration in sleep

Bull Eur Physiopathol Respir. Nov-Dec 1983;19(6):625-9.


15 subjects (mean age: 48.2 yr; 13 males, 2 females) with sleep apnea (12 obstructive, 3 central) were treated with an average dose of 2500 mg L-tryptophan (L-T) at bedtime. Comparison of pre- and post-drug polysomnograms showed significant improvement in obstructive sleep apnea but not with central sleep apnea. Most dramatic improvement is seen in subjects with obstructive sleep apnea in non-REM sleep only, but severity of apnea appears to be the most important factor determining improvement. L-T increased REM time and shortened REM latency but had no other significant effects on sleep architecture. Serotoninergic activity with a defect in feedback control of tryptophan-serotonin metabolism is postulated as a potential mechanism in the pathophysiology of obstructive sleep apnea. The enhanced usefulness of L-T in combination with protriptyline is predicted based on early preliminary work at the OSU Sleep Center. The Potential influence of dietary intake on respiratory automaticity is reviewed.

Publication types

  • Clinical Trial

MeSH terms

  • Clinical Trials as Topic
  • Diet
  • Drug Therapy, Combination
  • Feedback
  • Female
  • Humans
  • Male
  • Middle Aged
  • Monitoring, Physiologic
  • Obesity / complications
  • Protriptyline / administration & dosage
  • Serotonin / metabolism
  • Sleep Apnea Syndromes / drug therapy*
  • Sleep Apnea Syndromes / physiopathology
  • Sleep, REM
  • Tryptophan / administration & dosage
  • Tryptophan / metabolism
  • Tryptophan / therapeutic use*


  • Serotonin
  • Protriptyline
  • Tryptophan