Vitamin C as an adjuvant for treating major depressive disorder and suicidal behavior, a randomized placebo-controlled clinical trial

Trials. 2015 Mar 14;16:94. doi: 10.1186/s13063-015-0609-1.


Background: There are some animal studies suggesting the possible role of vitamin C for treating depression. However, the efficacy of vitamin C for treating adult patients with major depressive disorder (MDD) has never been examined.

Methods: This 8-week randomized double-blind placebo-controlled clinical trial included adult patients with major depressive disorder according to DSM-IV diagnostic criteria. Twenty-one patients in the treatment group received citalopram plus vitamin C and the 22 patients in the control group received citalopram plus placebo. The Hamilton Depression Rating Scale was used to measure depressive symptoms at baseline, week 2, week 4, and week 8. We also checked for the presence of adverse effects.

Results: While depression symptoms decreased in both groups during this trial, there was no statistically significant difference between the 2 groups (P = .5). The rate of remission, partial response, and complete response was not different between the two groups. The rate of adverse effects were not different between the two groups.

Conclusion: Adding vitamin C to citalopram did not increase the efficacy of citalopram in MDD patients. Vitamin C plus citalopram is as effective as placebo plus citalopram for treating adult patients with suicidal behavior. No serious adverse effect for this combination was identified during this trial.

Trial registration: This trial was registered at . The registration number of this trial was: IRCT201312263930N31 . Date registered: 5 July 2014.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Antidepressive Agents / adverse effects
  • Antidepressive Agents / therapeutic use*
  • Antioxidants / adverse effects
  • Antioxidants / therapeutic use*
  • Ascorbic Acid / adverse effects
  • Ascorbic Acid / therapeutic use*
  • Citalopram / adverse effects
  • Citalopram / therapeutic use*
  • Depressive Disorder, Major / diagnosis
  • Depressive Disorder, Major / drug therapy*
  • Depressive Disorder, Major / psychology
  • Double-Blind Method
  • Drug Therapy, Combination
  • Female
  • Humans
  • Male
  • Middle Aged
  • Suicidal Ideation*
  • Suicide / prevention & control*
  • Suicide / psychology
  • Time Factors
  • Treatment Outcome
  • Young Adult


  • Antidepressive Agents
  • Antioxidants
  • Citalopram
  • Ascorbic Acid

Associated data

  • IRCT/IRCT201312263930N31