Contraindications
There are few absolute contraindications to light therapy, although there are some circumstances in which caution is required. These include when the patient 1) has a condition that might render his or her eyes more vulnerable to phototoxicity, 2) has a tendency toward mania, 3) has a photosensitive skin condition, or 4) is taking a photosensitizing medication or herb. Patients with porphyria should avoid most forms of light therapy. Patients on certain drugs like methotrxate or chloroquine should use caution with light therapy as there is a chance that these drugs could cause porphyria.
Side effects
Side effects of light therapy for sleep phase disorders include jumpiness or jitteriness, feeling "wired," headache, and nausea. Some nondepressive physical complaints (such as poor vision and skin rash or irritation) may improve with light therapy (M. Terman and Terman 1999).