Summer seasonal affective disorder: a less common variant

Case scenario

Meredith, aged 50 years, complains of what she claims is ‘seasonal affective disorder’ (SAD). She describes a classic depression that starts suddenly, not in winter, but in November each year and then abruptly ceases in March. On questioning, she admits that the Christmas period is never a happy time for her due to longstanding family conflict. She has never been referred to a psychiatrist or psychologist and never been treated with any form of antidepressant. She has read about melatonin and wonders if it might help.

Can SAD occur in summer? What would be the appropriate management for this patient, and is melatonin likely to be of any use?