Hypnotics/sedatives associated with abnormal thinking and behavior changes, including decreased inhibition, aggression, bizarre behavior, agitation, hallucinations, and depersonalization (may indicate previously unrecognized psychiatric disorders). May cause CNS depression. Use of hypnotic/sedative agents (including ramelteon) for sleep associated with hypersensitivity reactions including anaphylaxis as well as angioedema. Patients who developed angioedema with ramelteon therapy should not be rechallenged. Reproductive hormonal regulation disturbances may cause disturbances of reproductive hormonal regulation (e.g. disruption of menses or decreased libido). Increased risk for hazardous sleep-related activities such as sleep-driving, cooking and eating food, and making phone calls while asleep also noted. Use with caution in depression (worsening of depression, including suicidal ideation reported with use of hypnotics), in hepatic impairment (use not recommended with severe impairment), and in respiratory compromise, COPD or sleep apnea. Use with caution in patients receiving other CNS depressants or psychoactive medication (effects with other sedative drugs or ethanol may be potentiated), and when administered concomitantly with strong CYP1A2 inhibitors. Rapid onset of action.