What are the treatment options for Seasonal Affective Disorder (SAD)?

Treatment for Seasonal Affective Disorder (SAD)

Bright light therapy is the first-line treatment for SAD, with bupropion extended-release as an FDA-approved pharmacologic alternative for prevention of seasonal depressive episodes. 1

Light Therapy: First-Line Treatment

Light therapy should be administered at 10,000 lux for 30 minutes daily in the morning, or alternatively 2,500 lux for 2 hours daily. 2, 3, 4

Optimal Light Therapy Protocol

• Morning administration is superior to evening treatment and should be the standard timing 2, 5
• Treatment typically begins in autumn, prior to onset of depressive symptoms, and continues through winter 1
• Response rates reach approximately 80% in selected patient populations, with atypical depressive symptoms predicting the best outcomes 5
• Traditional light boxes remain the standard, though newer whole-room BROAD (Bright, whole-ROom, All-Day) light therapy at higher illuminance levels shows promise for similar efficacy without confining patients to sitting in front of a device 6

Light Therapy Safety Profile

• Side effects are generally mild and include eyestrain, nausea, and agitation, with most resolving spontaneously 2
• Monitor closely for emergent hypomania, particularly in the first few days of treatment, as this is the most significant risk 2, 3
• Patients with eye disease or those taking photosensitizing medications require periodic ophthalmologic and dermatologic monitoring 2
• Headaches may occur but typically remit; however, light therapy can trigger migraines in approximately one-third of susceptible individuals 2

Pharmacologic Treatment

Bupropion Extended-Release (FDA-Approved for SAD)

Bupropion XL is FDA-approved specifically for prevention of seasonal major depressive episodes in SAD. 1

• Dosing protocol: Start 150 mg once daily in the morning; after 7 days, increase to target dose of 300 mg once daily 1
• Timing: Initiate in autumn prior to onset of depressive symptoms, continue through winter, then taper in early spring 1
• Tapering: Decrease from 300 mg to 150 mg once daily before discontinuing 1

Alternative Antidepressants

SSRIs (fluoxetine, sertraline) and moclobemide have demonstrated efficacy in randomized controlled trials for SAD. 5

• These medications show response rates comparable to light therapy in controlled studies 4, 5
• Antidepressants provide a compatible adjunct to light therapy, potentially resulting in accelerated improvement and fewer residual symptoms 3

Treatment Algorithm

Step 1: Initial Treatment Selection

• For most patients: Begin with morning light therapy (10,000 lux for 30 minutes) 2, 3, 4
• For patients preferring pharmacotherapy or unable to adhere to light therapy: Initiate bupropion XL 150 mg daily, increasing to 300 mg after 7 days 1

Step 2: Inadequate Response After 2-4 Weeks

• If partial response to light therapy alone: Add bupropion XL or an SSRI 3, 5
• If inadequate response to monotherapy: Combine light therapy with antidepressant medication 3

Step 3: Maintenance and Prevention

• Continue successful treatment regimen throughout winter season 1, 5
• Taper and discontinue in early spring as daylight increases 1
• Plan for reinitiation in subsequent autumn based on patient's historical pattern 1

Critical Pitfalls to Avoid

• Do not administer light therapy in the evening, as morning treatment has proven superior efficacy 2, 5
• Do not overlook monitoring for hypomania, especially in patients with bipolar disorder or family history of mania 2, 3
• Do not delay treatment initiation—begin in autumn before symptom onset for optimal prevention 1
• Do not use bupropion in patients with seizure disorders or eating disorders, as it lowers seizure threshold 1
• Ensure adequate treatment duration—brief trials of 1-2 weeks are insufficient; assess response after 2-4 weeks 6, 4

Emerging Evidence

Recent research suggests that higher illuminance levels in whole-room lighting configurations may enhance effectiveness, though this requires further validation 6. The 2022 VA/DoD guidelines now recommend bright light therapy for mild to moderate major depressive disorder regardless of seasonal pattern, expanding the potential application beyond traditional SAD 2.