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G-1 Side Effects

Generic name: acetaminophen / butalbital / caffeine

Medically reviewed by Drugs.com. Last updated on Nov 22, 2023.

Note: This document contains side effect information about acetaminophen / butalbital / caffeine. Some dosage forms listed on this page may not apply to the brand name G-1.

Applies to acetaminophen / butalbital / caffeine: oral capsule, oral solution, oral tablet.

Warning

Oral route (Capsule)

Liver failure, sometimes associated with liver transplant or fatalities, has occurred with acetaminophen use. These cases of liver injury were often associated with the use of more than 1 acetaminophen-based product and with total daily acetaminophen doses exceeding 4000 mg.

Serious side effects of G-1

Along with its needed effects, acetaminophen/butalbital/caffeine 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 acetaminophen / butalbital / caffeine:

More common

Incidence not known

Get emergency help immediately if any of the following symptoms of overdose occur while taking acetaminophen / butalbital / caffeine:

Symptoms of overdose

Other side effects of G-1

Some side effects of acetaminophen / butalbital / caffeine 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:

More common

Incidence not known

For Healthcare Professionals

Applies to acetaminophen / butalbital / caffeine: oral capsule, oral liquid, oral tablet.

Nervous system

Butalbital/Acetaminophen/Caffeine:

Common (1% to 10%): Drowsiness, lightheadedness, dizziness, sedation

Uncommon (0.1% to 1%): Headache, shaky feeling, tingly, fainting, numbness, seizures, mental confusion, excitement or depression due to intolerance

Caffeine:

Frequency not reported: Tremor[Ref]

General

The most frequently reported adverse events have included drowsiness, lightheadedness, dizziness, sedation, shortness of breath, nausea, vomiting, abdominal pain, and intoxicated feeling.[Ref]

Hepatic

Acetaminophen:

Frequency not reported: Liver failure[Ref]

Acute liver failure has been reported with acetaminophen use; many case have been associated with use at doses in excess of 4 g/day, and often involving more than 1 acetaminophen-containing product.[Ref]

Gastrointestinal

Common (1% to 10%): Nausea, vomiting, abdominal pain

Uncommon (0.1% to 1%): Dry mouth, difficulty swallowing, heartburn, flatulence, constipation[Ref]

Renal

Butalbital/Acetaminophen/Caffeine:

Uncommon (0.1% to 1%): Diuresis

Caffeine:

Frequency not reported: Nephrotoxicity[Ref]

Hypersensitivity

Uncommon (0.1% to 1%): Allergic reactions

Postmarketing reports: Anaphylaxis

Acetaminophen:

Postmarketing reports: Anaphylaxis[Ref]

Hematologic

Acetaminophen:

Frequency not reported: Thrombocytopenia, agranulocytosis[Ref]

Dermatologic

Butalbital/Acetaminophen/Caffeine:

Uncommon (0.1% to 1%): Hyperhidrosis, pruritus

Frequency not reported: Toxic epidermal necrolysis, erythema multiforme

Acetaminophen:

Rare (less than 0.1%): Serious skin reactions such as acute generalized exanthematous pustulosis, Stevens-Johnson syndrome, and toxic epidermal necrolysis

Frequency not reported: Rash[Ref]

Several cases of dermatologic reactions including toxic epidermal necrolysis and erythema multiforme have been reported.[Ref]

Respiratory

Common (1% to 10%): Shortness of breath

Uncommon (0.1% to 1%): Nasal congestion[Ref]

Cardiovascular

Butalbital/Acetaminophen/Caffeine:

Uncommon (0.1% to 1%): Tachycardia

Caffeine:

Frequency not reported: Cardiac stimulation[Ref]

Other

Common (1% to 10%): Intoxicated feeling

Uncommon (0.1% to 1%): Fatigue, high energy, heavy eyelids, sluggishness, hot spells, fever, earache, tinnitus[Ref]

Metabolic

Caffeine:

Frequency not reported: Hyperglycemia[Ref]

Musculoskeletal

Uncommon (0.1% to 1%): Leg pain, muscle fatigue[Ref]

Psychiatric

Butalbital/Acetaminophen/Caffeine:

Uncommon (0.1% to 1%): Agitation, euphoria

Caffeine:

Frequency not reported: Irritability, dependence[Ref]

References

1. (2022) "Product Information. Fioricet (acetaminophen / butalbital / caffeine)." Novartis Pharmaceuticals

2. (2016) "Product Information. Acetaminophen/Butalbital/Caffeine (acetaminophen / butalbital / caffeine)." Par Pharmaceutical Inc (formerly Qualitest Pharmaceuticals Inc)

3. (2016) "Product Information. Esgic (acetaminophen / butalbital / caffeine)." Forest Pharmaceuticals

4. (2016) "Product Information. Vanatol LQ (acetaminophen / butalbital / caffeine)." GM Pharmaceuticals

Further information

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.