Noontime Light for Bipolar Depression

Summary and Comment |
October 3, 2017

Noontime Light for Bipolar Depression

  1. Joel Yager, MD

Bright light at midday for 6 weeks produced remission in 68% of participants, compared with 22% receiving dim red light, with no mood switches.

  1. Joel Yager, MD

Because medications for bipolar depression are often ineffective and frequently produce adverse effects, nonpharmacological approaches hold great interest. Morning light in patients with bipolar depression has had mixed results and induces occasional hypomania. Based on preliminary work, investigators conducted a randomized, 6-week study comparing midday broad-spectrum bright-light therapy (7000 lux) with dim red light (a “sham” condition; 50 lux).

The 43 participants had moderate levels of bipolar depression with no manic symptoms and were on stable medications (mean age, 45; 67% female); 67% had bipolar I disorder, and 83% had some seasonality. Exclusions included manic, hypomanic, or mixed episodes within 6 months; rapid cycling in the past year; active psychosis, suicidality, or substance use disorder; and certain medical conditions.

Light therapy was daily between noon and 2:30 p.m., gradually increasing to a target of 60 minutes daily (median achieved length, 46 minutes). With most improvements occurring between weeks 4 and 6, 68% of those receiving bright light remitted at 6 weeks, compared with 22% receiving dim light. No hypomania, manic switches, or treatment-attributable serious adverse effects occurred.


Contrasting with studies reporting adverse effects or negative results with morning bright light in bipolar depression, this small study suggests that midday administration can be both effective and safe. The relatively late onset of benefits and the absent adverse effects might be due to the gradual up-titration of light dose. While these findings require replication and extension with larger samples, they suggest that add-on bright-light therapy administered at midday can help achieve remission in carefully selected patients with bipolar depression who are insufficiently improved with medications.

Editor Disclosures at Time of Publication

  • Disclosures for Joel Yager, MD at time of publication Editorial boards Bulletin of the Menninger Clinic; Eating Disorders Review; International Journal of Eating Disorders; UpToDate; FOCUS: The Journal of Lifelong Learning in Psychiatry


Your Comment

(will not be published)

Filtered HTML

  • Allowed HTML tags: <a> <em> <strong> <cite> <blockquote> <code> <ul> <ol> <li> <dl> <dt> <dd>
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.
Do you have any conflict of interest to disclose?
This question is for testing whether you are a human visitor and to prevent automated spam submissions.

Vertical Tabs

* Required

Reader comments are intended to encourage lively discussion of clinical topics with your peers in the medical community. We ask that you keep your remarks to a reasonable length, and we reserve the right to withhold publication of remarks that do not meet this standard.

PRIVACY: We will not use your email address, submitted for a comment, for any other purpose nor sell, rent, or share your e-mail address with any third parties. Please see our Privacy Policy.