Comparative study of efficacy of l-5-hydroxytryptophan and fluoxetine in patients presenting with first depressive episode

Asian J Psychiatr. 2013 Feb;6(1):29-34. doi: 10.1016/j.ajp.2012.05.011. Epub 2012 Jul 12.


Introduction: Role of l-5-hydroxytryptophan (l-5-HTP) in depression is relatively less studied but the literature has shown its robust role in depression. The present randomized double blind study was undertaken to assess the role of l-5-HTP as an antidepressant and to compare its antidepressant efficacy with fluoxetine in first depressive episode patients of Indian population.

Methods: A total of 70 patients of first depressive episode, all of whom were diagnosed with ICD-10 criteria, were recruited but only 60 patients completed the study and were randomly divided into two groups, receiving l-5-HTP and fluoxetine, respectively, for a period of 8weeks. All patients were administered Hamilton Rating Scale for Depression (HAM-D) to assess severity of depression at baseline, 2weeks, 4weeks and 8weeks. The efficacy of treatment was assessed by comparing HAM-D scores obtained at these examinations with the baseline examination; final evaluation of both efficacy and tolerance was assessed using the Clinical Global Impression (CGI) scale at the end of study.

Results: Both treatment groups showed significant and nearly equal reduction in HAM-D scores beginning at week two and continuing through week eight. Twenty-two patients (73.33%) in the l-5-HTP group and 24 patients (80%) in the fluoxetine group showed positive response at the end of the study.

Conclusion: l-5-HTP has definitely got antidepressant effect in patients of depression. Antidepressant effect was seen within 2weeks of treatment and was apparent in all degrees of depression. The therapeutic efficacy of l-5-HTP was considered as equal to that of fluoxetine.

Publication types

  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • 5-Hydroxytryptophan / administration & dosage
  • 5-Hydroxytryptophan / therapeutic use*
  • Adult
  • Antidepressive Agents, Second-Generation / administration & dosage
  • Antidepressive Agents, Second-Generation / therapeutic use*
  • Depressive Disorder / drug therapy*
  • Double-Blind Method
  • Fluoxetine / administration & dosage
  • Fluoxetine / therapeutic use*
  • Humans
  • Psychiatric Status Rating Scales
  • Surveys and Questionnaires
  • Time Factors
  • Treatment Outcome


  • Antidepressive Agents, Second-Generation
  • Fluoxetine
  • 5-Hydroxytryptophan