Light therapy for bipolar SAD needs a careful, low-and-slow approach

Light therapy for seasonal depression is tricky if you have bipolar disorder — the wrong dose can trigger hypomania or mixed states, but it’s not impossible to use safely.

The standard SAD protocol (10,000 lux, 30–60 minutes first thing in the morning) is too aggressive for many bipolar patients. The risk is real: bright morning light can shift your circadian rhythm too fast, pushing you into a high state. The same light that lifts a unipolar person out of winter blues can launch you into hypomania within days.

Here’s what I’ve seen work in practice:

• Use a lower intensity light box (2,500–5,000 lux) or sit farther away from your regular one.
• Start with 15 minutes and increase by 5 minutes every few days if you’re