On Aug. 13 the U.S. Food and Drug Administration announced the FDA approval of Belsomra (suvorexant) tablets for use as needed to treat insomnia, which involves difficulty in falling and staying asleep. Belsomra is an orexin receptor antagonist that alters the signaling of orexin in the brain. According to the FDA, it is the first approved drug of this type. The FDA has approved Belsomra in four different strengths:  5, 10, 15, and 20 milligrams.  The total dose should not exceed 20 mg once daily. The FDA cautions that patients taking Belsomra should be made aware of the potential for next-day driving impairment.