Zyban Side Effects

Generic name: bupropion

Medically reviewed by Drugs.com. Last updated on Sep 24, 2023.

Note: This document provides detailed information about Zyban Side Effects associated with bupropion. Some dosage forms listed on this page may not apply specifically to the brand name Zyban.

Applies to bupropion: oral tablet, oral tablet extended release, oral tablet extended release 12 hr, oral tablet extended release 24 hr.

Serious side effects of Zyban

Along with its needed effects, bupropion (the active ingredient contained in Zyban) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking bupropion:

Get emergency help immediately if any of the following symptoms of overdose occur while taking bupropion:

Symptoms of overdose

• lightheadedness, dizziness, or fainting
• loss of consciousness
• slow or irregular heartbeat
• unusual tiredness

Other side effects of Zyban

Some side effects of bupropion may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

For healthcare professionals

Applies to bupropion: oral tablet, oral tablet extended release.

General adverse events

In placebo-controlled clinical studies, the specific adverse events that led to discontinuation in at least 1% of patients treated with either 300 mg or 400 mg per day of Wellbutrin SR (R)included rash, nausea, agitation, and migraine. Additional events leading to discontinuation in the immediate-release formulation included mental state abnormalities, vomiting, seizures, headaches, and sleep disturbances, many of which occurred at doses greater than the recommended daily dose.

Adverse events leading to treatment discontinuation with Zyban (R) included tremors, and rashes. The most commonly observed adverse reactions were dry mouth and insomnia. Smoking cessation is often associated with nicotine withdrawal symptoms, some of which are also recognized as adverse events associated with bupropion (the active ingredient contained in Zyban) ^[Ref]

Psychiatric

• Very common (10% or more): Insomnia (up to 45%), agitation (up to 31.9%), abnormal dreams (up to 13%)
• Common (1% to 10%): Anxiety, confusion, decreased/increased libido, decreased memory/memory impairment, delusions, depression, disturbed concentration, dysphoria, euphoria, hallucinations, hostility, impaired sleep quality, irritability, mania/hypomania, nervousness, thinking abnormality
• Uncommon (0.1% to 1%): Aggression, bruxism, depersonalization, emotional lability, formal thought disorder, frigidity, mood instability, nightmares, paranoia, paranoid ideation, psychosis, suicidal ideation
• Rare (0.01% to 0.1%): Derealization, impaired attention
• Frequency not reported: Abnormalities in mental status, post-ictal confusion, sleep disturbances
• Postmarketing reports: Completed suicide, delirium, manic reaction, restlessness, suicidal behavior, suicide attempt^[Ref]

The Australian Adverse Drug Reaction Advisory Committee reported that 285 of the 780 reports it received in association with bupropion (the active ingredient contained in Zyban) through mid-May 2001 involved psychological disturbances.

Two cases of tactile hallucinations ("bugs crawling over skin") have been reported in association with bupropion extended-release (200 mg twice daily) therapy. In both cases the symptoms abated following a reduction in the total daily dose of bupropion (300 mg daily).

Insomnia may also be dose-dependent. In a dose response clinical study for smoking cessation, 29% of patients receiving bupropion 150 mg/day versus 35% of those receiving 300 mg/day reported insomnia. Insomnia may be minimized by reducing the dosage or avoiding administration at bedtime.^[Ref]

Nervous system

• Very common (10% or more): Headache (up to 34%), migraine (up to 25.7%), dizziness (up to 22.3%), tremor (up to 21.1%), sedation (up to 19.8%)
• Common (1% to 10%): Akathisia, ataxia/incoordination, central nervous system stimulation, dyskinesia, dystonia, feeling jittery, myoclonus, paresthesia, seizure, sensory disturbance, somnolence, syncope, taste disturbance, taste perversion
• Uncommon (0.1% to 1%): Abnormal coordination, dysarthria, hypesthesia, hyperkinesia, hypertonia, vertigo
• Rare (0.01% to 0.1%): Abnormal electroencephalogram, amnesia, parkinsonism
• Frequency not reported: Generalized tonic-clonic seizures
• Postmarketing reports: Akinesia, aphasia, coma, extrapyramidal syndrome, hypokinesia, neuropathy, neuralgia, unmasking tardive dyskinesia^[Ref]

The Australian Adverse Drug Reaction Advisory Committee reported that 268 of the 780 reports it received in association with bupropion through mid-May 2001 involved nervous system disorders.

Grand mal seizures have been reported in 0.4% of patients undergoing bupropion therapy at dosages up to 450 mg daily. The incidence of seizures increases dramatically at higher dosages. The seizure rate in patients taking sustained-release bupropion up to a dosage of 300 mg/day (e.g. for smoking cessation) has been approximated at 0.1%.

The risk of seizure appears to be dose-related. Other risk factors are related to patient factors e.g., severe head injury, arteriovenous malformation, CNS tumor or CNS infection, or severe stroke, concomitant medications that lower the seizure threshold (e.g., other bupropion products, antipsychotics, tricyclic antidepressants, theophylline, and systemic corticosteroids), metabolic disorders, illicit drug use, abuse or misuse of prescription drugs such as CNS stimulants, diabetes mellitus treated with oral hypoglycemics or insulin, treatment with anorectic drugs, and excessive use of alcohol, benzodiazepines, sedative/hypnotics, or opiates.

Two cases of elderly patients falling backwards have been attributed to the effects of bupropion on the basal ganglia.^[Ref]

Metabolic

• Very common (10% or more): Weight loss greater than 2.3 kg (up to 28%), weight gain greater than 2.3 kg (up to 11%)
• Common (1% to 10%): Anorexia, decreased appetite, increased appetite, thirst/thirst disturbance
• Rare (0.01% to 0.1%): Blood glucose disturbances
• Very rare (less than 0.01%): Hyponatremia
• Postmarketing reports: Hyperglycemia, hypoglycemia^[Ref]

Gastrointestinal

• Very common (10% or more): Dry mouth (up to 27.6%), constipation (up to 26%), nausea (up to 22.9%), vomiting (up to 22.9%)
• Common (1% to 10%): Abdominal pain, diarrhea, dyspepsia, dysphagia, flatulence, gastrointestinal disturbance, gustatory disturbance, mouth ulcer, stomatitis
• Uncommon (0.1% to 1%): Gastric reflux, gingivitis, gum irritation, increased salivation, inguinal hernia, oral edema, toothache
• Rare (0.01% to 0.1%): Edema of the tongue, intestinal perforation
• Frequency not reported: Esophagitis
• Postmarketing reports: Colitis, gastrointestinal hemorrhage, glossitis, gum hemorrhage, pancreatitis, stomach ulcer, stool abnormality^[Ref]

Dermatologic

• Very common (10% or more): Excessive sweating (up to 22.3%)
• Common (1% to 10%): Dry skin, facial edema, pruritus, rash, sweating, urticaria
• Uncommon (0.1% to 1%): Alopecia, ecchymosis, photosensitivity
• Rare (0.01% to 0.1%): Erythema multiforme, exacerbation of psoriasis, Stevens-Johnson syndrome
• Frequency not reported: Skin reactions
• Postmarketing reports: Exfoliative dermatitis, hirsutism, maculopapular rash^[Ref]

The Australian Adverse Drug Reaction Advisory Committee reported that 307 of the 780 reports it received in association with bupropion through mid- May 2001 involved skin reactions. Urticaria was the most commonly reported event (167 cases). Other rashes (86 cases) were also reported.^[Ref]

Local

• Very common (10% or more): Application site reaction (up to 15%)^[Ref]

Ocular

• Very common (10% or more): Blurred vision (up to 14.6%)
• Common (1% to 10%): Diplopia, visual disturbance
• Uncommon (0.1% to 1%): Accommodation abnormality, dry eye, mydriasis
• Postmarketing reports: Angle-closure glaucoma, increased intraocular pressure^[Ref]

Respiratory

• Very common (10% or more): Nasopharyngitis (up to 13%), rhinitis (up to 12%), pharyngitis (up to 11%)
• Common (1% to 10%): Bronchitis, cough, dyspnea/shortness of breath, epistaxis, increased cough, sinusitis, upper respiratory tract infection
• Rare (0.01% to 0.1%): Bronchospasm, pulmonary embolism
• Postmarketing reports: Pneumonia^[Ref]

Cardiovascular

• Very common (10% or more): Tachycardia (up to 11%)
• Common (1% to 10%): Cardiac arrhythmias, chest pain, edema, flushing, hot flashes, hypertension, hypotension, palpitations
• Uncommon (0.1% to 1%): Electrocardiogram abnormalities, nonspecific ST-T changes, peripheral edema, postural hypotension, premature beats, stroke, vasodilation
• Rare (0.01% to 0.1%): Myocardial infarction
• Postmarketing reports: Cardiovascular disorder, complete atrioventricular block, extrasystoles, orthostatic hypotension, phlebitis, severe hypertension, third degree heart block^[Ref]

In clinical practice, hypertension, in some cases severe, requiring acute treatment, has been reported in patients receiving bupropion alone and in combination with nicotine replacement therapy. These events have been observed in both patients with and without evidence of preexisting hypertension.

Some investigators have suggested that bupropion therapy may be 10 to 100 times less likely to induce conduction problems than tricyclic antidepressants.^[Ref]

Other

• Common (1% to 10%): Accidental injury, asthenia, auditory disturbance, chills, cutaneous temperature disturbance, fever, nonspecific fever, pain, temperature disturbance, tinnitus
• Uncommon (0.1% to 1%): Inguinal hernia, nonspecific pain
• Rare (0.01% to 0.1%): Malaise, overdose
• Postmarketing reports: Deafness^[Ref]

Genitourinary

• Common (1% to 10%): Decrease in sexual function, dysmenorrhea, impotence, menstrual complaints, nocturia, urinary frequency, urinary tract infection, urinary urgency, vaginal hemorrhage
• Uncommon (0.1% to 1%): Painful erection, polyuria, prostate disorder, retarded ejaculation, testicular swelling, vaginal irritation
• Rare (0.01% to 0.1%): Enuresis, urinary incontinence, urinary retention
• Postmarketing reports: Abnormal ejaculation, dyspareunia, dysuria, menopause, prostate disorder, salpingitis, urinary tract disorder, vaginitis^[Ref]

One study in which 150 patients received the sustained released form of bupropion (the active ingredient contained in Zyban) reported the incidence of orgasm dysfunction at 8% in patients receiving a 300 mg daily dose and 10% in patients receiving a 400 mg daily dose.

Among antidepressants, bupropion may be associated with the lowest incidence of sexual dysfunction (i.e., impotence, abnormal ejaculation, changes in libido).^[Ref]

Musculoskeletal

• Common (1% to 10%): Arthralgia, arthritis, myalgia, neck pain, pain in extremity, twitch/twitching
• Uncommon (0.1% to 1%): Leg cramps
• Postmarketing reports: Muscle rigidity, muscle weakness, musculoskeletal chest pain, rhabdomyolysis^[Ref]

Hypersensitivity

• Common (1% to 10%): Allergic reaction, hypersensitivity reactions
• Uncommon (0.1% to 1%): Fever with rash and other symptoms suggestive of delayed hypersensitivity
• Rare (0.01% to 0.1%): Angioedema, anaphylactic shock^[Ref]

Immunologic

• Common (1% to 10%): Flu-like symptoms, infection
• Uncommon (0.1% to 1%): Serum sickness-like reaction^[Ref]

Hepatic

• Uncommon (0.1% to 1%): Abnormal liver function, jaundice, liver damage
• Rare (0.01% to 0.1%): Elevated liver enzymes, hepatitis^[Ref]

Endocrine

• Uncommon (0.1% to 1%): Gynecomastia
• Frequency not reported: Syndrome of inappropriate antidiuretic hormone^[Ref]

Renal

• Rare (0.01% to 0.1%): Glycosuria
• Postmarketing reports: Cystitis^[Ref]

Hematologic

• Frequency not reported: Anemia, leukopenia, thrombocytopenia
• Postmarketing reports: Altered prothrombin time/INR with/without hemorrhagic/thrombotic complications, leukocytosis, lymphadenopathy, pancytopenia^[Ref]

Frequently asked questions

• How long does it take Wellbutrin XL/SR (bupropion) to work?
• Does Auvelity work better than Wellbutrin?
• Auvelity vs. Wellbutrin: Effectiveness for Depression?

Further information

Zyban side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.

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