Ramelteon is mainly used for the treatment of onset insomnia (difficulty falling asleep). It regulates the sleep-wake cycle by mimicking endogenous melatonin.

What Are the Side Effects of Ramelteon?

1. Nervous System Reactions

(1) Drowsiness (incidence: 5%).

(2) Dizziness (incidence: 5%).

(3) Fatigue (incidence: 4%).

2. Gastrointestinal Discomfort

(1) Nausea (incidence: 3%).

(2) Diarrhea (incidence: 2%).

3. Other Common Reactions

(1) Headache (incidence: 7%).

(2) Upper respiratory tract infection (incidence: 3%).

(3) Dysgeusia (abnormal taste, incidence: 2%).

(4) Muscle pain (incidence: 2%).

Serious Side Effects of Ramelteon Requiring Vigilance

1. Endocrine System Effects

Long-term use may lead to elevated prolactin levels, which can manifest as amenorrhea (absence of menstruation), galactorrhea (abnormal milk secretion), or decreased libido.

2. Psychobehavioral Abnormalities

(1) May exacerbate undiagnosed mental illnesses (e.g., depression, suicidal ideation).

(2) Rare cognitive and behavioral changes (e.g., sleepwalking, memory impairment).

3. Risks in Special Populations

(1) Patients with hepatic impairment: Exposure to Ramelteon increases by 10-fold in patients with moderate hepatic impairment; it is contraindicated in patients with severe hepatic impairment (Child-Pugh Class C).

(2) Respiratory diseases: Although it does not worsen mild to moderate COPD (chronic obstructive pulmonary disease) or sleep apnea, data on severe cases is lacking.

4. Risk of Drug Interactions

Concomitant use with potent CYP1A2 inhibitors (e.g., fluvoxamine) can cause a 190-fold surge in Ramelteon’s blood concentration, which is an absolute contraindication.

Precautions for Ramelteon Use

1. Administration Regimen

(1) Standard dosage: 8 mg taken 30 minutes before bedtime.

(2) Dietary impact: High-fat meals increase the AUC (area under the concentration-time curve) of Ramelteon by 31%, so concurrent intake with high-fat foods should be avoided.

(3) Treatment duration recommendation: Short-term use is recommended (usually ≤ 35 days); long-term use requires monitoring of endocrine function.

2. Contraindicated Populations

(1) Patients allergic to Ramelteon or its excipients.

(2) Patients with severe hepatic insufficiency.

(3) Patients currently taking fluvoxamine.

3. Pre-Administration Assessment

(1) Screen for potential mental illnesses and respiratory diseases.

(2) Hepatic function tests (dose reduction is required for patients with moderate hepatic impairment).

4. Monitoring During Administration

(1) Female patients with abnormal menstruation or galactorrhea should undergo prolactin testing.

(2) Monitor emotional changes (especially in patients with depression).

5. Safety Warnings

(1) After taking the medication, go to bed immediately and avoid nighttime activities.

(2) Avoid alcohol consumption (alcohol may enhance central depressant effects).