chronotherapeutics

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Medical treatment administered according to a schedule that corresponds to a person's daily, monthly, seasonal, or yearly biological clock, in order to maximize the health benefits and minimize adverse effects.
2. n. Treatment of a sleep disorder by altering an individual's sleeping and waking times and resetting his or her biological clock.

Wiktionary

1. n. medicine Any of several forms of therapy that is administered in phase with a person's biological clock