SIDE EFFECTS
Commonly Observed
The most commonly reported adverse events associated with the use of Butalbital, Aspirin, Caffeine,
and Codeine Phosphate Capsules, USP and not reported at an equivalent incidence by placebo-treated
patients were nausea and/or abdominal pain, drowsiness, and dizziness.
Associated With Treatment Discontinuation
Of the 382 patients treated with Butalbital, Aspirin, Caffeine, and Codeine Phosphate Capsules, USP in
controlled clinical trials, three (0.8%) discontinued treatment with Butalbital, Aspirin, Caffeine, and
Codeine Phosphate Capsules, USP because of adverse events. One patient each discontinued treatment
for the following reasons: gastrointestinal upset; lightheadedness and heavy eyelids; and drowsiness
and generalized tingling.
Incidence In Controlled Clinical Trials
The following table summarizes the incidence rates of the adverse events reported by at least 1% of the
Butalbital, Aspirin, Caffeine, and Codeine Phosphate Capsules, USP treated patients in controlled
clinical trials comparing Butalbital, Aspirin, Caffeine, and Codeine Phosphate Capsules, USP to
placebo, and provides a comparison to the incidence rates reported by the placebo-treated patients.
The prescriber should be aware that these figures cannot be used to predict the incidence of side
effects in the course of usual medical practice where patient characteristics and other factors differ
from those that prevailed in the clinical trials. Similarly, the cited frequencies cannot be compared with
figures obtained from other clinical investigations involving different treatments, uses, and
investigators.
Adverse Events Reported by at Least 1% of Butalbital, Aspirin, Caffeine, and Codeine Phosphate
Capsules , USP Treated Patients During Placebo Controlled Clinical Trial
Body System/Adverse Event |
Incidence Rate of Adverse Events Butalbital, Aspirin, Caffeine, and Codeine Phosphate Capsules, USP
(N = 382) |
Placebo
(N = 377) |
Central Nervous |
Drowsiness |
2.4% |
0.5% |
Dizziness/Lightheadedness |
2.6% |
0.5% |
Intoxicated Feeling |
1.0% |
0% |
Gastrointestinal |
Nausea/Abdominal Pain |
3.7% |
0.8% |
Other Adverse Events Reported During Controlled Clinical Trials
The listing that follows represents the proportion of the 382 patients exposed to Butalbital, Aspirin,
Caffeine, and Codeine Phosphate Capsules, USP while participating in the controlled clinical trials who
reported, on at least one occasion, an adverse event of the type cited. All reported adverse events,
except those already presented in the previous table, are included. It is important to emphasize that,
although the adverse events reported did occur while the patient was receiving Butalbital, Aspirin,
Caffeine, and Codeine Phosphate Capsules, USP, the adverse events were not necessarily caused by
Butalbital, Aspirin, Caffeine, and Codeine Phosphate Capsules, USP.
Adverse events are classified by body system and frequency. “Frequent” is defined as an adverse event
which occurred in at least 1/100 (1%) of the patients; all adverse events listed in the previous table are
frequent. “Infrequent” is defined as an adverse event that occurred in less than 1/100 patients but at least
1/1000 patients. All adverse events tabulated below are classified as infrequent.
Central Nervous : headache, shaky feeling, tingling, agitation, fainting, fatigue, heavy eyelids, high
energy, hot spells, numbness, and sluggishness.
Autonomic Nervous: dry mouth and hyperhidrosis.
Gastrointestinal: vomiting, difficulty swallowing, and heartburn.
Cardiovascular: tachycardia.
Musculoskeletal: leg pain and muscle fatigue.
Genitourinary: diuresis.
Miscellaneous: pruritus, fever, earache, nasal congestion, and tinnitus.
Voluntary reports of adverse drug events, temporally associated with Butalbital, Aspirin, Caffeine, and
Codeine Phosphate Capsules, USP, that have been received since market introduction and that were not
reported in clinical trials by the patients treated with Butalbital, Aspirin, Caffeine, and Codeine
Phosphate Capsules, USP, are listed below. Many or most of these events may have no causal
relationship with the drug and are listed according to body system.
Central Nervous: Abuse, addiction, anxiety, depression, disorientation, hallucination, hyperactivity,
insomnia, libido decrease, nervousness, neuropathy, psychosis, sedation, sexual activity increase,
slurred speech, twitching, unconsciousness, vertigo.
Autonomic Nervous: epistaxis, flushing, miosis, salivation.
Gastrointestinal: anorexia, appetite increased, constipation, diarrhea, esophagitis, gastroenteritis,
gastrointestinal spasm, hiccup, mouth burning, pyloric ulcer.
Cardiovascular: chest pain, hypotensive reaction, palpitations, syncope.
Skin: erythema, erythema multiforme, exfoliative dermatitis, hives, rash, toxic epidermal necrolysis.
Urinary: kidney impairment, urinary difficulty.
Miscellaneous: allergic reaction, anaphylactic shock, cholangiocarcinoma, drug interaction with
erythromycin (stomach upset), edema.
The following adverse drug events may be borne in mind as potential effects of the components of
Butalbital, Aspirin, Caffeine, and Codeine Phosphate Capsules, USP. Potential effects of high dosage
are listed in the OVERDOSAGE section of this insert.
Aspirin: occult blood loss, hemolytic anemia, iron deficiency anemia, gastric distress, heartburn,
nausea, peptic ulcer, prolonged bleeding time, acute airway obstruction, renal toxicity when taken in
high doses for prolonged periods, impaired urate excretion, hepatitis.
Caffeine: cardiac stimulation, irritability, tremor, dependence, nephrotoxicity, hyperglycemia.
Codeine: nausea, vomiting, drowsiness, lightheadedness, constipation, pruritus.