What the label lists and what reports show
Acetaminophen and butalbital side effects
Acetaminophen and butalbital's FDA label: “The most frequently reported adverse reactions are drowsiness, lightheadedness, dizziness, sedation, shortness of breath, nausea, vomiting, abdominal pain, and intoxicated feeling.” FAERS holds 602 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is fatigue (72 reports).
- Generic listed
- Boxed warning
- DEA Schedule III
Check it at the source: the acetaminophen and butalbital FDA label on DailyMed (effective May 6, 2024, QUAGEN PHARMACEUTICALS LLC); the FDA FAERS public dashboard.
What does the label list?
From the label: adverse reactionsThe most frequently reported adverse reactions are drowsiness, lightheadedness, dizziness, sedation, shortness of breath, nausea, vomiting, abdominal pain, and intoxicated feeling.
From the label: adverse reactions, continuedFrequently Observed The most frequently reported adverse reactions are drowsiness, lightheadedness, dizziness, sedation, shortness of breath, nausea, vomiting, abdominal pain, and intoxicated feeling. Infrequently Observed 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, sluggishness, seizure. Mental confusion, excitement or depression can also occur due to intolerance, particularly in elderly or debilitated patients, or due to overdosage of butalbital. Autonomic Nervous System: dry mouth, hyperhidrosis. Gastrointestinal: difficulty swallowing, heartburn, flatulence, constipation. Cardiovascular: tachycardia. Musculoskeletal: leg pain, muscle fatigue. Genitourinary: diuresis. Miscellaneous: pruritus, fever, earache, nasal congestion, tinnitus, euphoria, allergic reactions. Several cases of dermatological reactions, including toxic epidermal necrolysis and erythema multiforme, have been reported. The following adverse drug events may be borne in mind as potential effects of the components of this product. Potential effects of high dosage are listed in the OVERDOSAGE section. A cetaminophen: allergic reactions, rash, thrombocytopenia, agranulocytosis. …
Source: FDA drug label, QUAGEN PHARMACEUTICALS LLC, effective May 6, 2024 (SPL set 2eb09253-7f59-401e-afbc-70bb9600fedf), via openFDA; the full label on DailyMed
What do FAERS reports show?
602 reports list acetaminophen and butalbital among the medicines taken, each a report of something that happened, not proof the medicine caused it; 48 are coded as a death and 140 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 20 reactions below, 6 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Acetaminophen and butalbital: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions