Ramelteon is a melatonin receptor agonist used for the treatment of sleep-onset insomnia.

I. Common Side Effects

Common adverse reactions (incidence ≥3% and higher than placebo) include: somnolence, dizziness, fatigue, nausea, and worsened insomnia.

II. Serious Side Effects Requiring Vigilance

1. Severe Allergic Reactions:

(1) Rare cases of angioedema involving the tongue, glottis, or larynx have been reported, with some patients experiencing dyspnea, throat tightness, nausea, vomiting, and other anaphylactoid symptoms.

(2) If the tongue, glottis, or larynx is involved, fatal airway obstruction may occur.

2. Abnormal Thinking and Behavioral Changes:

(1) Hallucinations, bizarre behavior, agitation, mania, amnesia, and anxiety may occur.

(2) Special attention is required for "sleep driving" (driving a vehicle while not fully awake after taking the medication) and other complex behaviors (preparing food, making phone calls, having sex), often accompanied by subsequent amnesia.

3. Worsening of Psychiatric Conditions:

Patients with pre-existing depression may experience worsening depression and suicidal ideation.

4. Central Nervous System Effects:

After taking the medication, activities requiring high mental alertness, such as operating machinery or driving a vehicle, may be impaired.

5. Reproductive Endocrine Effects:

(1) Can lead to decreased testosterone levels and increased prolactin levels.

(2) In females: amenorrhea, galactorrhea; in males or females: decreased libido, fertility problems.

III. Stratified Management of Side Effects

1. Management of Allergic Reactions:

(1) If swelling of the tongue or throat, or difficulty breathing occurs, discontinue the drug immediately and go to the emergency room.

(2) Patients with a prior history of angioedema should never use this medication again.

2. Management of Complex Sleep Behaviors:

(1) If sleep driving, eating while asleep, or other abnormal behaviors occur, inform your doctor immediately and consider discontinuing the drug.

(2) Absolutely avoid alcohol while taking this medication, as alcohol significantly increases the risk of such behaviors.

3. Management of Psychiatric Symptoms:

(1) Patients with pre-existing depression or psychiatric disorders should have close monitoring of mood and behavioral changes during treatment.

(2) If suicidal thoughts or worsening of behavior occurs, seek medical attention immediately.

4. Management of Daytime Drowsiness:

(1) Drowsiness may persist into the next day after dosing. It is recommended not to drive or operate hazardous machinery until fully awake.

(2) In most patients, residual daytime effects resolve spontaneously after 5 weeks of continuous use.

5. Monitoring Endocrine Changes:

(1) If amenorrhea, galactorrhea, decreased libido, or fertility problems occur, prolactin and testosterone levels should be checked.

(2) These changes are usually reversible upon discontinuation of the drug.

6. Countermeasures for Worsened Insomnia:

If insomnia has not improved after 7 to 10 days of treatment, or if worsened insomnia or cognitive/behavioral abnormalities appear, this may indicate an underlying undiagnosed condition and a reassessment of the diagnosis is required.

IV. Emergency Indications for Discontinuation

Discontinue the drug and seek medical attention immediately if any of the following occur: swelling of the tongue or throat with difficulty breathing; first occurrence of sleep driving or eating while asleep; suicidal ideation or severe worsening of depression; amenorrhea, galactorrhea, or significant decrease in libido.

V. Drug Storage Environmental Requirements

1. Temperature Conditions:

Store at room temperature around 25°C, allowed to vary between 15°C and 30°C.

2. Moisture Protection:

Keep container tightly closed to protect from moisture and humidity.

3. Light Protection:

Avoid direct sunlight and high temperatures; maintain the integrity of the original packaging.

4. Expiration Date:

Follow the expiration date on the drug label. Do not use expired medication.