Bupropion medical uses:
Bupropion hydrochloride, an antidepressant of the aminoketone class, is chemically unrelated to tricyclic, tetracyclic, selective serotonin re-uptake inhibitor, or other known antidepressant agents. Its structure closely resembles that of diethylpropion; it is related to phenylethylamines.

Bupropion Sustained-Release is indicated for the treatment of major depressive disorder and smoking cessation. Sometimes this antidepressants is prescribed for weight loss, bipolar depression, fibromyalgia, and headaches.

Contraindications:

seizure disorder
current or prior diagnosis of bulimia or anorexia nervosa
concurrent treatment with or within 14 days of discontinuation of MAO inhibitors
concurrent treatment with multiple bupropion products (ie, coadministration of Zyban for smoking cessation and Wellbutrin for depression)
abrupt discontinuation of alcohol or sedatives
hypersensitivity to bupropion or any other component of the product.

Bupropion dosage:

The SR formulation of bupropion is taken twice a day, in order to decrease the possibility of negative side effects and seizures.

Depression:

Immediate-release: 100 mg two times per day initially; may increase to 100 mg tree times per day after 3 days (max daily dose, 450 mg; max single dose, 150 mg).

Sustained-release: 150 mg once daily initially; may increase to 150 mg two times per day as early as day 4 of therapy (max daily dose, 400 mg; max single dose, 200 mg).

Extended-release: 150 mg once daily initially; may increase to 300 mg once daily as early as day 4 of therapy (max daily dose, 450 mg).

Dosing conversion between immediate, sustained, and extended release products: Convert using same total daily dose (up to the maximum recommended dose for a given dosage form), but adjust frequency as indicated for sustained (twice daily) or extended (once daily) release products.

Foods: May be taken without regard to meals.

Side effects:

Cardiovascular: tachycardia (11%); palpitation (6%); cardiac arrhythmia (5%); flushing, hypertension (4%); hot flashes, hypotension (3%); syncope (1%); edema (at least 1%); orthostatic hypotension, third degree heart block (postmarketing).
Dermatologic: sweating (22%); rash (8%); pruritus (4%); urticaria (2%); nonspecific rashes (at least 1%); angioedema, exfoliative dermatitis, Stevens-Johnson syndrome (postmarketing).
Central nervous system: agitation (32%); insomnia (31%); headache (26%); dizziness (22%); tremor (21%); sedation (20%); disturbed concentration (9%); akinesia/bradykinesia, anxiety, confusion (8%); hostility (6%); fatigue, nervousness (5%); impaired sleep quality, migraine, sensory disturbances (4%); decreased libido, decreased memory, irritability, somnolence (3%); CNS stimulation, paresthesia (2%); delusions (1%); ataxia/incoordination, decreased sexual function, depression, dyskinesia, dystonia, hallucinations, increased libido, mania/hypomania, myoclonus, seizure (at least 1%); abnormal dreams, coma, delirium, paresthesia, restlessness, unmasking tardive dyskinesia (postmarketing).
Gastrointestinal: dry mouth (28%); constipation (26%); nausea/vomiting (23%), weight loss (23%), anorexia (18%), weight gain (14%), abdominal pain (9%); diarrhea (7%); increased appetite, taste perversion, vomiting (4%); dyspepsia, gustatory disturbance (3%); dysphagia (2%); stomatitis (at least 1%); esophagitis (postmarketing).
Genitourinary: urinary frequency, menstrual complaints (5%); impotence (3%); urinary retention, urinary urgency, vaginal hemorrhage (2%); UTI (1%); nocturia (at least 1%).
Musculoskeletal: myalgia (6%); arthralgia (4%); arthritis (3%); akathisia, muscle spasm, twitch (2%); arthralgia, muscle rigidity, muscle weakness, myalgia, rhabdomyolysis (postmarketing) .
Special senses: blurred vision (15%), tinnitus (5%), auditory disturbance (5%).
Respiratory: upper respiratory infection (9%), pharyngitis (3%), cough increased (1-4%), sinusitis (1-5%).
Hematologic-Lymphatic: altered PT or INR, ecchymosis, leukocytosis, leukopenia, thrombocytopenia (postmarketing).

Precautions:

Children. Bupropion is not FDA approved for use in children.
Elderly. Use with caution. Because elderly patients are more likely to have decreased renal function, use care in dose selection and consider monitoring renal function.
Bipolar depression. May worsen psychosis in some patients or precipitate a shift to mania or hypomania in patients with bipolar disorder.
Renal & Hepatic Function. Use with caution; reduce frequency and/or dose as needed.\
Cardiovascular effects. Use caution in patients with cardiovascular disease, history of hypertension, or coronary artery disease; treatment-emergent hypertension (including some severe cases) has been reported.
Seizures. The risk of seizures is dose-dependent and increased in patients with a history of seizures, anorexia/bulimia, head trauma, CNS tumor, severe hepatic cirrhosis, abrupt discontinuation of sedative-hypnotics or ethanol, medications which lower seizure threshold (antipsychotics, antidepressants, theophyllines, systemic steroids), stimulants, or hypoglycemic agents.

Drug interactions:

Alcohol: Adverse neuropsychiatric events or reduced alcohol tolerance may occur. The consumption of alcohol during treatment with bupropion should be minimized or avoided.
Amantadine, levodopa: Incidence of bupropion side effects may be increased.
Drugs that lower seizure threshold (antipsychotics, other antidepressants, theophylline, systemic steroids, etc.): Concurrent administration these agents with bupropion and agents should be undertaken only with extreme caution. Low initial dosing and small gradual dose increases should be employed.
Anticonvulsants (carbamazepine, phenobarbital, phenytoin): May decrease bupropion serum concentrations.
CYP2B6 inhibitors (clopidogrel, cyclophosphamide, orphenadrine, thiotepa, ticlopidine): May increase bupropion plasma levels and risk of adverse effects.
MAO inhibitors, selegiline: Risk of acute bupropion toxicity.
Metoprolol: Risk of bradycardia.
Nicotine Transdermal System: Risk of hypertension.
Warfarin: Risk of hemorrhagic or thrombotic complications.

Pregnancy & Lactation

Pregnancy category C
A slight increase in malformations was observed in some animal studies.
In studies conducted in rats and rabbits, bupropion was administered orally at doses up to 450 and 150 mg/kg/day, respectively (approximately 11 and 7 times the maximum recommended human dose), during the period of organogenesis. No clear evidence of teratogenic activity was found in either species; however, in rabbits, slightly increased incidences of fetal malformations and skeletal variations were observed at the lowest dose tested (25 mg/kg/day, approximately equal to the MRHD) and greater. Decreased fetal weights were seen at 50 mg/kg and greater.

One study has been conducted in pregnant women. This retrospective, managed-care database study assessed the risk of congenital malformations overall, and cardiovascular malformations specifically, following exposure to bupropion in the first trimester compared to the risk of these malformations following exposure to other antidepressants in the first trimester and bupropion outside of the first trimester. This study included 7,005 infants with antidepressant exposure during pregnancy, 1,213 of whom were exposed to bupropion in the first trimester. The study showed no greater risk for congenital malformations overall, or cardiovascular malformations specifically, following first trimester bupropion exposure compared to exposure to all other antidepressants in the first trimester, or bupropion outside of the first trimester. The results of this study have not been corroborated. Bupropion should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Nursing mothers
Bupropion and its metabolites are secreted in human milk. Because of the potential for serious adverse reactions in nursing infants from bupropion, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.

Overdose:
Contact your doctor or pharmacist immediately. Symptoms of overdose may include cardiac arrest, ECG changes or arrhythmias, hallucinations, loss of consciousness, seizures, sinus tachycardia.

Missed dose:
If a dose is missed, take it as soon as possible. If several hours have passed or if it is nearing time for the next dose, do not double the dose to catch up, unless advised by your doctor. If more than one dose is missed, contact your doctor or pharmacist.

Storage:
Store it at room temperature and away from excess heat and moisture (not in the bathroom).

How and Where to Buy:
If you would like to order Bupropion SR without prescription, choose the offer from the above table.

References:

1. U.S. Food and Drug Administration. Wellbutrin XL U.S. Prescribing Information. Available at (PDF format)
2. U.S. Food and Drug Administration. Wellbutrin SR U.S. Prescribing Information. Available at (PDF format)