Few photosensitive reactions caused by pyridoxine hydrochloride have been reported. There have been no reports of detailed photosensitivity studies on patients who have developed photosensitivity from pharmacologic doses of pyridoxine. Two patients with pyridoxine photosensitivity are described. Photopatch tests were positive for pyridoxine hydrochloride. The minimal erythematous dose (MED) for UVA decreased after the intravenous injection of pyridoxine hydrochloride in both patients. Normal controls gave negative results in photopatch tests for pyridoxine hydrochloride and phototest for vitamin B complex containing pyridoxine hydrochloride. On the basis of these results, we believe both patients had a photoallergic reaction to pyridoxine hydrochloride.