What is Wellbutrin/Bupropion?
Tablets of the anti-depressant drug Wellbutrin
Wellbutrin, Wellbutrin SR, Wellbutrin XL, Zyban
DRUG CLASS AND MECHANISM:
Bupropion is a prescription drug sold under the brand names Wellbutrin® (Wellbutrin, Wellbutrin XL, and Wellbutrin XR) and Zyban®. Bupropion under the name Wellbutrin is approved for use as an anti-depressant. Bupropion under the name Zyban is approved for use as a smoking cessation treatment.
A recent study published in the American Journal of Obstetrics & Gynecology found that women who took bupropion during the first trimester of pregnancy may be at increased risk of giving birth to a baby with congenital heart defects.
Bupropion is an antidepressant medication that affects chemicals within the brain that nerves use to send messages to each other. These chemical messengers are called neurotransmitters. Many experts believe that depression is caused by an imbalance among the amounts of neurotransmitters that are released. Nerves, in a process referred to as reuptake, may recycle released neurotransmitters. Bupropion works by inhibiting the reuptake of dopamine, serotonin, and norepinephrine; an action that results in more dopamine, serotonin, and norepinephrine to transmit messages to other nerves. Bupropion is unique and unlike other antidepressants in that its major effect is on dopamine, an effect that is not shared by the selective serotonin reuptake inhibitors or SSRIs [for example, paroxetine (Paxil), fluoxetine (Prozac), sertraline (Zoloft)] or the tricyclic antidepressants or TCAs [for example, amitriptyline (Elavil), imipramine (Tofranil), desipramine (Norpramin)]. The FDA approved bupropion in December 1985.
Bupropion is used for the management of major depression and seasonal affective disorder (depression that occurs primarily during the fall and winter). It is also prescribed for smoking cessation.
Bupropion usually is given in one, two or three daily doses. For immediate-release tablets, no single dose should exceed 150 mg and each dose should be separated by 6 hours.
For depression the recommended dose of immediate-release tablets is 100 mg 3 times daily (300 mg/day); maximum dose is 450 mg daily. The initial dose is 100 mg twice daily. The dose may be increased to 100 mg 3 times daily after three days.
The initial dose of sustained-release tablets is 150 mg daily; target dose is 150 mg twice daily; maximum dose is 200 mg twice daily.
The initial dose of extended-release tablets is 150 mg daily; target dose is 300 mg daily; maximum dose is 450 mg daily. Extended release tablets are administered once daily.
When used for smoking cessation, bupropion usually is started as 150 mg once daily for three days, and then the dose is increased if the patient tolerates the starting dose. Smoking is discontinued two weeks after starting bupropion therapy.
Wellbutrin SR is given as two daily doses. Wellbutrin XL is given as one dose daily.
Bupropion should be used cautiously in patients receiving drugs that reduce the threshold for seizures. Such drugs include prochlorperazine (Compazine), chlorpromazine (Thorazine), and other antipsychotic medications of the phenothiazine class. Additionally, persons who are withdrawing from benzodiazepines [for example, diazepam (Valium), alprazolam (Xanax)] are at increased risk for seizures.
Carbamazepine (Tegretol) may reduce the effect of bupropion by reducing the blood concentration of bupropion. Monamine oxidase inhibitors should not be combined with bupropion because of the risk of severe reactions. At least 14 days should elapse between discontinuation of an MAOI and initiation of bupropion. Bupropion may affect the action of warfarin (Coumadin).
Selective serotonin reuptake inhibitors during
pregnancy and risk of persistent pulmonary
hypertension in the newborn
Persistent pulmonary hypertension of the newborn is a life
threatening condition that occurs in up to 2 per 1000 liveborn
infants and most often in those born full term or post term.1-3 In
this condition the pulmonary vascular resistance fails to decrease
after birth and the ductus arteriosus must remain open to ensure
circulation. Persistent pulmonary hypertension of the newborn
and persistent fetal circulation are often used synonymously.
Click to read full research paper (pdf)