Ramelteon is a selective melatonin receptor agonist, primarily used for the treatment of insomnia characterized by difficulty falling asleep. As a prescription drug, its use must strictly comply with medical advice.

What Are the Side Effects of Ramelteon?

Common Side Effects

Drowsiness (3%).

Dizziness (4%).

Fatigue (3%).

Nausea (3%).

Worsened insomnia (3%).

Severe Side Effects of Ramelteon Requiring Vigilance

Severe Allergic Reactions

Rare but life-threatening angioedema (e.g., swelling of the tongue or throat) and anaphylactic reactions, accompanied by symptoms such as difficulty breathing and vomiting.

If such reactions occur, discontinue the drug immediately, seek medical attention, and never use the drug again.

Abnormal Behaviors and Psychiatric Symptoms

Complex sleep behaviors: Including sleepwalking, sleep driving, unconscious eating or sexual activity, which may be accompanied by memory loss.

Psychiatric abnormalities: Hallucinations, mania, worsening depression (including suicidal tendencies).

Cognitive impairment: Decreased attention and memory loss.

Effects on the Endocrine System

Long-term use may decrease testosterone levels and increase prolactin levels, leading to reduced libido, menstrual irregularities, or abnormal breast milk secretion.

Respiratory Risks

Contraindicated in patients with severe sleep apnea: It may exacerbate the condition.

Caution required in patients with moderate to severe chronic obstructive pulmonary disease (COPD).

Central Nervous System Depression

Alertness may be impaired after taking the drug; avoid driving or operating machinery.

Precautions for Ramelteon Administration

Contraindications

Patients allergic to ramelteon or those who have experienced angioedema.

Concomitant use with potent CYP1A2 inhibitors (e.g., fluvoxamine) is prohibited.

Drugs Contraindicated for Concomitant Use

Alcohol (exacerbates central nervous system depression).

Fluvoxamine (significantly increases the plasma concentration of ramelteon).

Drugs Requiring Caution for Concomitant Use

Ketoconazole (a CYP3A4 inhibitor) and fluconazole (a CYP2C9 inhibitor) — increase ramelteon exposure.

Donepezil and doxepin — close monitoring for adverse reactions is required.

Rifampicin (a CYP inducer) — may reduce therapeutic efficacy.

Other Precautions

Dietary impact: Avoid taking with high-fat meals (which delay absorption and reduce efficacy).

Treatment course management: If insomnia does not improve within 7–10 days, re-evaluate the cause.

Laboratory tests: For patients on long-term treatment, regular monitoring of hormone levels (e.g., prolactin, testosterone) is recommended.