Yuandakang Bupropion Hydrochloride Sustained-release Tablets (II)

1. Indications and Usage
Major Depressive Disorder (MDD): Treatment of depressive episodes in adult patients.
Smoking Cessation: Used as an aid to smoking cessation treatment to reduce the frequency of cravings and withdrawal symptoms in adult patients.
2. Dosage and Administration
Route of Administration: Oral administration ONLY.
Administration for MDD:
Starting Dose: 150 mg once daily in the morning.
Titration: After 4 days, the dose may be increased to 300 mg once daily in the morning.
Administration for Smoking Cessation:
Starting Dose: 150 mg once daily for the first 3 days.
Titration: From Day 4 to Day 7, increase to 150 mg twice daily (with an interval of >8 hours between doses). From Day 8 onwards, maintain at 150 mg once or twice daily.
Target Quit Date: Set for the second week of treatment (usually Day 8).
Critical Administration Instructions:
Swallowing: Tablets must be swallowed whole. Do not crush, chew, or break the tablet.
Timing: Administer in the morning to avoid insomnia. If taking twice daily, ensure the second dose is taken in the early afternoon with an interval of at least 8 hours.
Discontinuation: Patients receiving 300 mg/day should taper the dose to 150 mg/day before completely stopping the medication.
3. Mechanism of Action
NDRI Activity: Bupropion is a selective inhibitor of the neuronal reuptake of norepinephrine and dopamine.
Neurotransmitter Modulation: It has minimal effect on the reuptake of serotonin and does not inhibit monoamine oxidase (MAO).
Therapeutic Effect: The enhancement of noradrenergic and dopaminergic transmission is believed to contribute to its antidepressant effects and its efficacy in reducing nicotine craving and withdrawal symptoms.
4. Safety and Warnings
Seizure Risk: Bupropion causes a dose-related risk of seizure. The risk is significantly increased in patients with eating disorders (anorexia nervosa or bulimia), a history of seizures, or those taking other drugs that lower the seizure threshold.
Suicidal Thoughts and Behaviors: Antidepressants increase the risk of suicidal thinking and behavior in children, adolescents, and young adults. Close monitoring for clinical worsening and behavioral changes is required, especially during initial treatment or dose adjustments.
Neuropsychiatric Reactions: May cause agitation, anxiety, insomnia, irritability, hostility, and manic episodes. Patients should be monitored for emergent neuropsychiatric symptoms.
Hypertension: May cause elevated blood pressure, particularly when used concomitantly with nicotine replacement therapy. Regular blood pressure monitoring is recommended.
5. Adverse Reactions and Clinical Research
Most Common Adverse Reactions: Dry mouth, insomnia, headache, nausea, vomiting, constipation, tremor, sweating, anxiety, agitation, dizziness, and tinnitus.
Adverse Reactions Leading to Discontinuation: Flushing, nausea, agitation, and migraine.
Clinical Research Highlights: Clinical trials have demonstrated that bupropion is effective in treating depression without causing the sexual dysfunction or weight gain commonly associated with SSRIs. In smoking cessation, it has been proven to significantly increase abstinence rates compared to placebo.
6. Drug Interactions
MAO Inhibitors: Contraindicated. A minimum washout period of 14 days is required between stopping an MAOI and starting bupropion, and vice versa.
CYP2B6 Substrates: Bupropion is primarily metabolized by CYP2B6 and can inhibit this enzyme. Concomitant use with CYP2B6 substrates (e.g., thioridazine, tamoxifen) may increase their plasma concentrations.
Drugs Lowering Seizure Threshold: Extreme caution is required when co-administered with antipsychotics, other antidepressants, systemic corticosteroids, or theophylline.
Nicotine Transdermal Patches: Concomitant use may increase the incidence of treatment-emergent hypertension; blood pressure should be closely monitored.
7. Pharmaceutical Information
Chemical Composition: Active Ingredient: Bupropion Hydrochloride.
Appearance: White to off-white or pale yellow film-coated tablets (often imprinted with “150 XL” or “300 XL”).
Packaging: Available in 150 mg and 300 mg extended-release tablets.
Storage: Store at or below 25°C in a dry place; protect from light.