Bupropion hydrochloride
Bupropion hydrochloride (Wellbutrin)
Bupropion hydrochloride
(byou- PROH-pee-on)
Pregnancy Category: B Wellbutrin Wellbutrin SR Zyban (Rx)

Classification: Antidepressant, miscellaneous; smoking deterrent

Action/Kinetics: Mechanism of action is not known; the drug does not inhibit MAO and it only weakly blocks neuronal uptake of epinephrine, serotonin, and dopamine. Exerts moderate anticholinergic and sedative effects, but only slight orthostatic hypotension. Peak plasma levels: 2-3 hr. t 1/2: 8-24 hr. Time to steady state: Within 8 days. Significantly metabolized by a first-pass effect through the liver to both active and inactive metabolites. Can induce drug-metabolizing enzymes. During chronic use the plasma levels of two active metabolites may be higher than bupropion. Excreted through both the urine (87%) and the feces (10%). Zyban is a sustained-release formulation.

Uses: Short-term (6 weeks or less) treatment of depression. Aid to stop smoking (may be combined with a nicotine transdermal system).

Contraindications: Seizure disorders; presence or history of bulimia or anorexia nervosa due to the higher incidence of seizures in such clients. Concomitant use of an MAO inhibitor. Wellbutrin, Wellbutrin SR, and Zyban all contain bupropion; do not use together. Lactation.

Special Concerns: Use with caution in clients with cranial trauma, with drugs that lower the seizure threshold (e.g., alcohol use; addiction to opiates, cocaine, or stimulants; use of OTC stimulants and anorectics, antipsychotics, other antidepressants, theophylline, systemic steroids; diabetes treated with oral hypoglycemics or insulin), and situations that might cause seizures (e.g., abrupt cessation of a benzodiazepine). Use with caution and in lower doses in clients with liver or kidney disease and in those with a recent history of MI or unstable heart disease. Safety and efficacy have not been established in clients less than 18 years of age.

Side Effects: Listed are side effects with an incidence of 0.1% or greater. CNS: Agitation, restlessness, anxiety, insomnia, headache, migraine, dizziness, seizures, excessive sweating, tremor, sedation, akinesia, bradykinesia, nervousness, sensory disturbances, impaired sleep quality, somnolence, irritability, decreased memory, pseudoparkinsonism, akathisia, hyperkinesia, paresthesia, CNS stimulation, confusion, hostility, disturbed concentration, increased or decreased libido, delusions, euphoria, ataxia, dyskinesia, dystonia, hypertonia, hypesthesia, vertigo, depersonalization, dysphoria, suicidal ideation, mania/hypomania, incoordination, myoclonus, hallucinations, depression, psychosis, unstable moods, paranoia, formal thought disorder, frigiditiy. GI: Constipation, weight loss or gain, N&V;, anorexia, dry mouth, diarrhea, increased appetite, dyspepsia, dysphagia, increased salivary flow, stomatitis, bruxism, glossitis, thirst disturbance, jaundice, liver damage, toothache, gum irritation, oral edema, gastric reflux, gingivitis, mouth ulcers, thirst, taste perversion. CV: Tachycardia, cardiac arrhythmias, hypertension, palpitations, hypotension, syncope, ECG abnormalities, chest pain. Respiratory: Pharyngitis, sinusitis, increased cough, upper respiratory complaints, shortness of breath, dyspnea, bronchitis. Musculoskeletal: Arthritis, myalgia, arthralgia, twitch/muscle spasms, musculoskeletal chest pain. GU: Menstrual complaints, impotence, urinary frequency, urinary retention, urinary urgency, vaginal hemorrhage, urinary tract infection, vaginal irritation, testicular swelling, painful erection, retarded ejaculation, polyuria, prostate disorder. Dermatologic: Rash, pruritus, urticaria, flushing, hot flushes, rashes, angioedema, exfoliative dermatitis, alopecia, dry skin, ecchymosis. Ophthalmic: Blurred vision, amblyopia, visual disturbances, abnormal accommodation, dry eye. Otic: Auditory disturbance, tinnitus. Miscellaneous: Infection, fatigue, pain, fever, chills, cutaneous temperature disturbance, flu-like symptoms, nonspecific pain.

Overdose Management: Symptoms: Seizures, hallucinations, loss of consciousness, tachycardia, multiple uncontrolled seizures, bradycardia, fever, muscle rigidity, hypotension, rhabdomyolosis, stupor, coma, respiratory failure, cardiac failure and cardiac arrest prior to death. Treatment: Client should be hospitalized. If conscious, syrup of ipecac is given to induce vomiting followed by activated charcoal q 6 hr during the first 12 hr after ingestion. Monitor both ECG and EEG for 48 hr; fluid intake must be adequate. If the client is in a stupor, is comatose, or is convulsing, gastric lavage may be undertaken provided intubation of the airway has been performed. Seizures may be treated with IV benzodiazepines and other supportive procedures.

Drug Interactions: Alcohol / Seizure threshold; may precipitate seizures Amantadine / Psychotic reactions Carbamazepine / Bupropion metabolism plasma levels Cimetidine / Inhibits metabolism of bupropion Fluoxetine / Panic symptoms and psychotic reactions Levodopa / Risk of side effects MAO inhibitors / Acute toxicity to bupropion may , especially. with phenelzine Phenobarbital / Bupropion metabolism plasma levels Phenytoin / Bupropion metabolism plasma levels Retonavir / Risk of bupropion toxicity Tricyclic antidepressants (TCAs) / Plasma levels of TCAs side effects

How Supplied: Tablet: 75 mg, 100 mg; Tablet Extended Release: 100 mg, 150 mg

Dosage
?Tablets, Immediate Release Antidepressant.
Adults, initial: 100 mg in the morning and evening for the first 3 days; then, 100 mg t.i.d., given in the morning, midday, and in the evening (6 hr should elapse between doses). If no response is observed after 4 weeks or longer, the dose may be increased to 450 mg/day with individual doses not to exceed 150 mg. Doses higher than 450 mg should not be administered. Maintenance: Lowest dose to control depression. Several months of treatment may be necessary.
?Tablets, Sustained Release Antidepressant.
Adults, initial: 150 mg once daily in the a.m. If 150 mg is tolerated, increase to 300 mg/day given as 150 mg b.i.d., allowing 8 or more hr between successive doses. Do not exceed a daily dose of 400 mg given as 200 mg b.i.d. in clients where no clinical improvement was noted after several weeks of 300 mg/day.
Smoking deterrent.
Begin dosing at 150 mg/day for the first 3 days followed by 150 mg b.i.d. Eight hours or more should elapse between successive doses.