Incidence of Commonly Observed Adverse Events in Controlled Clinical Trials
In placebo-controlled clinical trials, 9% and 11% of patients treated with
300 and 400 mg/day, respectively, of the sustained-release formulation of bupropion
and 4% of patients treated with placebo discontinued treatment due to adverse
The specific adverse events in these trials that led to discontinuation
in at least 1% of patients treated with either 300 mg/day or 400 mg/day of the
sustained-release formulation of bupropion, and at a rate at least twice the
placebo rate are listed in Table 4.
Table 4. Treatment Discontinuations Due to Adverse Events
in Placebo-Controlled Trials
(n = 376)
(n = 114)
(n = 385)
In clinical trials with the immediate-release formulation of bupropion, 10%
of patients and volunteers discontinued due to an adverse event. Events resulting
in discontinuation, in addition to those listed above for the sustained-release
formulation of bupropion, include vomiting, seizures, and sleep disturbances.
Adverse Events Occurring at an Incidence of 1% or More Among Patients Treated
With the Immediate-Release or Sustained-Release Formulations of Bupropion
Table 5 enumerates treatment-emergent adverse events that occurred among
patients treated with 300 and 400 mg/day of the sustained-release formulation
of bupropion and with placebo in controlled trials.
Events that occurred in
either the 300 or 400 mg/day group at an incidence of 1% or more and were more
frequent than in the placebo group are included. Reported adverse events were
classified using a COSTART-based Dictionary.
Accurate estimates of the incidence of adverse events associated with the use
of any drug are difficult to obtain. Estimates are influenced by drug dose,
detection technique, setting, physician judgments, etc.
The figures cited cannot
be used to predict precisely the incidence of untoward events in the course
of usual medical practice where patient characteristics and other factors differ
from those that prevailed in the clinical trials.
These incidence figures also
cannot be compared with those obtained from other clinical studies involving
related drug products as each group of drug trials is conducted under a different
set of conditions.
Finally, it is important to emphasize that the tabulation does not reflect
the relative severity and/or clinical importance of the events. A better perspective
on the serious adverse events associated with the use of bupropion is provided
in the WARNINGS and PRECAUTIONS sections.
Table 5. Treatment-Emergent Adverse Events in Placebo-Controlled
|Body System/Adverse Event||Sustained-release
bupropion 300 mg/day
(n = 376)
bupropion 400 mg/day
(n = 114)
(n = 385)
|Central nervous System stimulation||2%||1%||1%|
|Urinary tract Infection||1%||0%||—|
| * Adverse events that occurred in at least
1% of patients treated with either 300 or 400 mg/day of the sustained-release
formulation of bupropion, but equally or more frequently in the placebo
group, were: abnormal dreams, accidental injury, acne, appetite increased,
back pain, bronchitis, dysmenorrhea, dyspepsia, flatulence, flu syndrome,
hypertension, neck pain, respiratory disorder, rhinitis, and tooth disorder.
† Incidence based on the number of female patients.
— Hyphen denotes adverse events occurring in greater than 0 but less
than 0.5% of patients.
Additional events to those listed in Table 5 that occurred at an incidence
of at least 1% in controlled clinical trials of the immediate-release formulation
of bupropion (300 to 600 mg/day) and that were numerically more frequent than
cardiac arrhythmias (5% vs 4%), hypertension (4% vs 2%), hypotension
(3% vs 2%), tachycardia (11% vs 9%), appetite increase (4% vs 2%), dyspepsia
(3% vs 2%), menstrual complaints (5% vs 1%), akathisia (2% vs 1%), impaired
sleep quality (4% vs 2%), sensory disturbance (4% vs 3%), confusion (8% vs 5%),
decreased libido (3% vs 2%), hostility (6% vs 4%), auditory disturbance (5%
vs 3%), and gustatory disturbance (3% vs 1%).
Adverse events from Table 5 occurring in at least 5% of patients treated
with the sustained-release formulation of bupropion and at a rate at least twice
the placebo rate are listed below for the 300 and 400 mg/day dose groups.
300 mg/day of the Sustained-Release Formulation:Anorexia, dry
mouth, rash, sweating, tinnitus, and tremor.
400 mg/day of the Sustained-Release Formulation: Abdominal pain,
agitation, anxiety, dizziness, dry mouth, insomnia, myalgia, nausea, palpitation,
pharyngitis, sweating, tinnitus, and urinary frequency.