Ramelteon is a selective MT1/MT2 melatonin receptor agonist, indicated for the treatment of insomnia characterized by difficulty falling asleep.
How to Use Ramelteon
Standard Administration Regimen
Dosage: The recommended dose is 8mg, taken orally within 30 minutes before bedtime.
Dosage form: 8mg film-coated tablets, containing excipients such as lactose and starch; the tablets should be swallowed whole.
Timing of administration: Avoid taking with high-fat meals (which can increase AUC by 31% and decrease Cmax by 22%).
Operational Precautions
Management of missed dose: If the scheduled dose is missed, take it as soon as possible before bedtime; resume the original scheduled timing the next day.
Contraindicated combinations: Concurrent use with strong CYP1A2 inhibitors (e.g., fluvoxamine) is prohibited (as this can increase AUC by 190-fold).
Precautions for Taking Ramelteon
Dosage Adjustment for Patients with Hepatic Insufficiency
Mild hepatic impairment: No dosage adjustment is required, but careful monitoring is necessary.
Moderate hepatic impairment: Use with caution (drug exposure increases by more than 10-fold).
Severe hepatic impairment (Child-Pugh Class C): Use is contraindicated.
Management of Adverse Reactions
Common reactions: Somnolence (5%), dizziness (5%), fatigue (4%); usually no need to discontinue the medication.
Endocrine effects: Long-term use may increase prolactin levels (an average increase of 34% in women); attention should be paid to symptoms such as abnormal menstruation or galactorrhea (milk secretion from the breasts).
Severe reactions: If signs of allergy or liver injury (e.g., jaundice, elevated transaminases) occur, discontinue the medication immediately.
Drug Interactions
Enzyme inducers (e.g., rifampicin): May reduce efficacy; alternative treatment options should be evaluated.
Central nervous system depressants (e.g., alcohol): Enhance sedative effects; concurrent use should be avoided.
Ramelteon Use in Special Populations
Elderly Patients
Dosage: Same as in adults (8mg), but note that AUC may increase by 97% (especially in patients aged ≥75 years).
Monitoring: Pay attention to residual effects the next day (e.g., fatigue, memory loss).
Pregnancy and Lactation
Pregnancy: Animal studies show a risk of teratogenicity (diaphragmatic hernia at doses ≥150mg/kg); human data are limited. Use is only permitted when the benefits are significantly greater than the risks.
Lactation: Ramelteon is excreted in rat milk; excretion in human milk is unknown. It is recommended to either discontinue the medication or stop breastfeeding.
Patients with Respiratory Diseases
Mild to moderate COPD/sleep apnea: May be used, but data on severe cases are lacking.
Severe sleep apnea: Use is not recommended.

