Drug Guide
Bupropion Hydrochloride; Dextromethorphan Hydrobromide
Classification
Therapeutic: Antidepressant, Cough Suppressant
Pharmacological: Norepinephrine-Dopamine Reuptake Inhibitor (Bupropion), NMDA Receptor Antagonist (Dextromethorphan)
FDA Approved Indications
- Major Depressive Disorder (MDD)
Mechanism of Action
Bupropion acts as a norepinephrine-dopamine reuptake inhibitor, increasing the levels of these neurotransmitters in the brain. Dextromethorphan acts as an NMDA receptor antagonist and sigma-1 receptor agonist, providing antidepressant effects and cough suppression.
Dosage and Administration
Adult: The typical starting dose is 45 mg of dextromethorphan and 105 mg of bupropion once daily at bedtime, titrated according to response and tolerability. It may be adjusted based on clinical response and side effects.
Pediatric: Not approved for use in pediatric patients.
Geriatric: Use caution; consider lower starting doses due to increased risk of side effects and comorbidities.
Renal Impairment: Adjust dose based on severity; consult prescribing information.
Hepatic Impairment: Use caution; no specific adjustments recommended; monitor closely.
Pharmacokinetics
Absorption: Rapidly absorbed after oral administration.
Distribution: Widely distributed in body tissues, crosses the blood-brain barrier.
Metabolism: Metabolized in the liver primarily via CYP2B6 for bupropion, and via other hepatic pathways for dextromethorphan.
Excretion: Renal elimination of metabolites; half-life approximately 21 hours for bupropion and 3-6 hours for dextromethorphan.
Half Life: Approximately 21 hours for bupropion; 3-6 hours for dextromethorphan.
Contraindications
- History of seizure disorder
- Bulimia or anorexia nervosa
- Concurrent use of monoamine oxidase inhibitors (MAOIs)
- Hypersensitivity to components
Precautions
- Use with caution in patients with hepatic impairment, psychosis, or a history of suicidal thoughts. Monitor for hyponatremia and neuropsychiatric symptoms.
Adverse Reactions - Common
- Nausea (Common)
- Dry mouth (Common)
- Dizziness (Common)
- Insomnia (Common)
Adverse Reactions - Serious
- Seizures (Rare)
- Suicidal thoughts or behavior (Rare)
- Hypertension (Rare)
- Serotonin syndrome (if combined with serotonergic drugs) (Rare)
Drug-Drug Interactions
- MAOIs, other antidepressants, antipsychotics, CYP2B6 inhibitors or inducers
Drug-Food Interactions
- Alcohol, which may increase CNS depression and seizure risk
Drug-Herb Interactions
N/ANursing Implications
Assessment: Monitor mood, suicidal thoughts, blood pressure, and signs of seizure risk.
Diagnoses:
- Risk for injury (seizures)
- Risk for suicide
Implementation: Administer medication as prescribed. Educate patient on seizure risk and adherence.
Evaluation: Assess effectiveness in managing depression symptoms. Monitor for adverse effects.
Patient/Family Teaching
- Take medication exactly as prescribed.
- Report signs of allergic reactions, worsening depression, or seizure activity.
- Avoid alcohol and other CNS depressants.
- Be aware of potential side effects and adverse reactions.
Special Considerations
Black Box Warnings:
- Increased risk of suicidal thoughts and behaviors in children, adolescents, and young adults.
- Risk of seizure at higher doses or in susceptible individuals.
Genetic Factors: Metabolism of bupropion via CYP2B6 may vary; genetic polymorphisms can affect drug levels.
Lab Test Interference: May increase liver enzymes; monitor as clinically indicated.
Overdose Management
Signs/Symptoms: Seizures, altered mental status, hallucinations, coma.
Treatment: Supportive care, airway management, seizure control with benzodiazepines, activated charcoal if within appropriate time frame, and gastric lavage as needed.
Storage and Handling
Storage: Store at room temperature 20-25°C (68-77°F), away from moisture and light.
Stability: Stable for the duration of the expiration date when stored properly.