Acetaminophen

INDICATIONS AND USAGE Butalbital, acetaminophen and caffeine capsules are indicated for the relief of the symptom complex of tension (or muscle contraction) headache. Evidence supporting the efficacy and safety of this combination product in the treatment of multiple recurrent headaches is unavailable. Caution in this regard is required because butalbital is habit-forming and potentially abusable.

DOSAGE AND ADMINISTRATION One or two capsules every four hours. Total daily dosage should not exceed 6 capsules. Extended and repeated use of this product is not recommended because of the potential for physical dependence.

CONTRAINDICATIONS This product is contraindicated under the following conditions: Hypersensitivity or intolerance to any component of this product. Patients with porphyria.

WARNINGS Butalbital is habit-forming and potentially abusable. Consequently, the extended use of this product is not recommended. Hepatotoxicity Acetaminophen has been associated with cases of acute liver failure, at times resulting in liver transplant and death. Most of the cases of liver injury are associated with the use of acetaminophen at doses that exceed 4000 milligrams per day, and often involve more than one acetaminophen-containing product. The excessive intake of acetaminophen may be intentional to cause self-harm or unintentional as patients attempt to obtain more pain relief or unknowingly take other acetaminophen-containing products. The risk of acute liver failure is higher in individuals with underlying liver disease and in individuals who ingest alcohol while taking acetaminophen. Instruct patients to look for acetaminophen or APAP on package labels and not to use more than one product that contains acetaminophen. Instruct patients to seek medical attention immediately upon ingestion of more than 4000 milligrams of acetaminophen per day, even if they feel well. Serious Skin Reactions Rarely, acetaminophen may cause serious skin reactions such as acute generalized exanthematous pustulosis (AGEP), Stevens-Johnson Syndrome (SJS), and toxic epidermal necrolysis (TEN), which can be fatal. Patients should be informed about the signs of serious skin reactions, and use of the drug should be discontinued at the first appearance of skin rash or any other sign of hypersensitivity. Hypersensitivity/anaphylaxis There have been post-marketing reports of hypersensitivity and anaphylaxis associated with use of acetaminophen. Clinical signs included swelling of the face, mouth, and throat, respiratory distress, urticaria, rash, pruritus, and vomiting. There were infrequent reports of life-threatening anaphylaxis requiring emergency medical attention. Instruct patients to discontinue butalbital, acetaminophen and caffeine capsules immediately and seek medical care if they experience these symptoms. Do not prescribe butalbital, acetaminophen, and caffeine capsules for patients with acetaminophen allergy.

Drug Interactions The CNS effects of butalbital may be enhanced by monoamine oxidase (MAO) inhibitors. Butalbital, acetaminophen and caffeine may enhance the effects of: other narcotic analgesics, alcohol, general anesthetics, tranquilizers such as chlordiazepoxide, sedative-hypnotics, or other CNS depressants, causing increased CNS depression.

ADVERSE REACTIONS Frequently 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 System: 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. Acetaminophen: allergic reactions, rash, thrombocytopenia, agranulocytosis. Caffeine: cardiac stimulation, irritability, tremor, dependence, nephrotoxicity, hyperglycemia.

Pregnancy Teratogenic Effects Animal reproduction studies have not been conducted with this combination product. It is also not known whether butalbital, acetaminophen and caffeine can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. This product should be given to a pregnant woman only when clearly needed. Nonteratogenic Effects Withdrawal seizures were reported in a two-day-old male infant whose mother had taken a butalbital-containing drug during the last two months of pregnancy. Butalbital was found in the infant's serum. The infant was given phenobarbital 5 mg/kg, which was tapered without further seizure or other withdrawal symptoms.