bupropion

Bupropion (Wellbutrin) is an antidepressant medication that affects chemicals within the brain that nerves use to send messages to each other.

Bupropion (Wellbutrin) 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 in 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 transmitting messages to other nerves.

Bupropion is used for the management of major depression (major depressive disorder) and seasonal affective disorder (depression that occurs primarily during the fall and winter). It is also prescribed for smoking cessation.

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, Endep], imipramine [Tofranil], desipramine [Norpramin]). The FDA approved bupropion in December 1985.

Off-label uses (non-FDA approved) for bupropion include posttraumatic stress disorder (PTSD), anxiety, attention deficit hyperactivity disorder (ADHD), social phobia, and nerve pain (neuropathic pain).

WARNING

Four of every 1000 persons who receive bupropion in doses less than 450 mg/day experience seizures. When doses exceed 450 mg/day, the risk increases tenfold. Other risk factors for seizures include past injury to the head and medications that can lower the threshold for seizures. (See drug interactions.)

Antidepressants increased the risk of suicidal thinking and behavior (suicidality) in short-term studies in children and adolescents with depression and other psychiatric disorders. Anyone considering the use of bupropion or any other antidepressant in a child or adolescent must balance this risk with the clinical need. Patients who are started on therapy should be closely observed for clinical worsening, suicidality, or unusual changes in behavior.

The most common side effects associated with bupropion include:

• Weight loss
• Skin rash
• Sweating
• Ringing in the ears (tinnitus)
• Shakiness
• Stomach pain
• Dizziness
• Muscle pain
• Fast heartbeat
• Sore throat
• Frequent urination
• Agitation
• Dry mouth
• Insomnia
• Headache
• Nausea
• Constipation
• Tremor

In some people, agitation or insomnia is most marked shortly after starting therapy.

Less common side effects include:

• Chest pain
• Fever
• Flushing
• Hot flashes
• Migraine
• Problems swallowing
• Twitching
• Arthritis
• Myalgia
• Nervousness
• Sinusitis
• Hives
• Urinary tract infections

More serious side effects include:

• High blood pressure (hypertension)
• Unusual thoughts or behaviors (hallucinations, paranoia, feeling confused.

Bupropion immediate-release tablets are usually 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.

Depression

• For depression, the recommended dose of immediate-release tablets is 100 mg 3 times daily (300 mg/day); the 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 and 150 mg 3 times after several weeks if the initial response is not adequate.
• The initial dose of sustained-release tablets is 150 mg daily; the target dose is 150 mg twice daily; the maximum dose is 200 mg twice daily.
• The initial dose of extended-release tablets is 150 mg daily; the target dose is 300 mg daily; the maximum dose is 450 mg daily. Extended-release tablets are administered once daily.
• Some patients with depression may be switched from bupropion hydrochloride (Wellbutrin, for example) to bupropion hydrobromide (Aplenzin) while others may need doses higher than those listed above. The correct dose of these medications for you should be determined by your doctor.

Smoking cessation

• When used for smoking cessation, bupropion (Zyban) usually is started at 150 mg once daily for three days, and then the dose is increased to 150 mg twice daily for 7 to 12 weeks if the patient tolerates the starting dose. Smoking is discontinued two weeks after starting bupropion therapy.

Seasonal affective disorder

• The dose for seasonal affective disorder is 150 mg once daily up to 300 mg daily using bupropion hydrochloride extended-release tablets (for example, Wellbutrin XL). Alternatively, treatment may be started with 174 mg bupropion hydrobromide (Aplenzin) daily and increased to a target dose of 348 mg per day. Start treatment in the autumn before the onset of seasonal depressive symptoms and continue through the winter season.

• 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).
• Ritonavir (Norvir) may increase the breakdown and elimination of bupropion. In some studies, ritonavir reduced the concentration of bupropion in the body by 22% to 66%.

There are no adequate studies of bupropion in pregnant women. In one study, there was no difference between bupropion and other antidepressants in the occurrence of birth defects. Bupropion should only be used in pregnancy if the benefit outweighs the potential risk.

Bupropion is secreted in breast milk.

Preparations

Bupropion is available as over 50 Brand names in the US, therefore, there are many formulations. Examples of these formulations/combinations include bupropion, bupropion hydrochloride, and/or bupropion hydrobromide either as a single active chemical or in combination with another (like Contrave).

These are the most common formulations available in the US:

• Bupropion hydrochloride immediate-release tablets: 75 and 100 mg.
• Bupropion Sustained Release (SL) tablets: 100, 150, and 200 mg.
• Bupropion Extended Release (XL) tablets: 150 and 300, and 450mg. (Forfivo XL)
• Bupropion hydrobromide (Aplenzin) tablets: 174, 348, and 522mg.

Other formulations/prescriptions of bupropion may be available. Examine the prescription label on your prescription bottle to be sure it is what your doctor has ordered. Ask your doctor or pharmacist any questions you have regarding this drug.

Other bupropion information

• Tablets should be kept at room temperature, 15 C to 25 C (59 F to 77 F).
• Wellbutrin, Wellbutrin SR, Wellbutrin XL, Zyban, Aplenzin, Forfivo XL, and Zyban are the brand names available for bupropion in the US.
• Bupropion is available as a generic drug.
• Bupropion requires a prescription from a doctor or pharmacist.