NORPACE® Adverse Reactions

(disopyramide phosphate capsules)

ADVERSE REACTIONS

The adverse reactions which were reported in Norpace clinical trials encompass observations in 1,500 patients, including 90 patients studied for at least 4 years. The most serious adverse reactions are hypotension and congestive heart failure. The most common adverse reactions, which are dose dependent, are associated with the anticholinergic properties of the drug. These may be transitory, but may be persistent or can be severe. Urinary retention is the most serious anticholinergic effect.

The following reactions were reported in 10% to 40% of patients:

Anticholinergic: dry mouth (32%), urinary hesitancy (14%), constipation (11%)

The following reactions were reported in 3% to 9% of patients:

Anticholinergic: blurred vision, dry nose/eyes/throat

Genitourinary: urinary retention, urinary frequency and urgency

Gastrointestinal: nausea, pain/bloating/gas

General: dizziness, general fatigue/muscle weakness, headache, malaise, aches/pains

The following reactions were reported in 1% to 3% of patients:

Genitourinary: impotence

Cardiovascular: hypotension with or without congestive heart failure, increased congestive heart failure (see Warnings), cardiac conduction disturbances (see Warnings), edema/weight gain, shortness of breath, syncope, chest pain

Gastrointestinal: anorexia, diarrhea, vomiting

Dermatologic: generalized rash/dermatoses, itching

Central nervous system: nervousness

Other: hypokalemia, elevated cholesterol/triglycerides

The following reactions were reported in less than 1%:

Depression, insomnia, dysuria, numbness/tingling, elevated liver enzymes, AV block, elevated BUN, elevated creatinine, decreased hemoglobin/hematocrit

Hypoglycemia has been reported in association with Norpace administration (see Warnings).

Infrequent occurrences of reversible cholestatic jaundice, fever, and respiratory difficulty have been reported in association with disopyramide therapy, as have rare instances of thrombocytopenia, reversible agranulocytosis, and gynecomastia. Some cases of LE (lupus erythematosus) symptoms have been reported; most cases occurred in patients who had been switched to disopyramide from procainamide following the development of LE symptoms. Rarely, acute psychosis has been reported following Norpace therapy, with prompt return to normal mental status when therapy was stopped. The physician should be aware of these possible reactions and should discontinue Norpace or Norpace CR therapy promptly if they occur.

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Adverse Reactions

ADVERSE REACTIONS

The adverse reactions which were reported in Norpace clinical trials encompass observations in 1,500 patients, including 90 patients studied for at least 4 years. The most serious adverse reactions are hypotension and congestive heart failure. The most common adverse reactions, which are dose dependent, are associated with the anticholinergic properties of the drug. These may be transitory, but may be persistent or can be severe. Urinary retention is the most serious anticholinergic effect.

The following reactions were reported in 10% to 40% of patients:

Anticholinergic: dry mouth (32%), urinary hesitancy (14%), constipation (11%)

The following reactions were reported in 3% to 9% of patients:

Anticholinergic: blurred vision, dry nose/eyes/throat

Genitourinary: urinary retention, urinary frequency and urgency

Gastrointestinal: nausea, pain/bloating/gas

General: dizziness, general fatigue/muscle weakness, headache, malaise, aches/pains

The following reactions were reported in 1% to 3% of patients:

Genitourinary: impotence

Cardiovascular: hypotension with or without congestive heart failure, increased congestive heart failure (see Warnings), cardiac conduction disturbances (see Warnings), edema/weight gain, shortness of breath, syncope, chest pain

Gastrointestinal: anorexia, diarrhea, vomiting

Dermatologic: generalized rash/dermatoses, itching

Central nervous system: nervousness

Other: hypokalemia, elevated cholesterol/triglycerides

The following reactions were reported in less than 1%:

Depression, insomnia, dysuria, numbness/tingling, elevated liver enzymes, AV block, elevated BUN, elevated creatinine, decreased hemoglobin/hematocrit

Hypoglycemia has been reported in association with Norpace administration (see Warnings).

Infrequent occurrences of reversible cholestatic jaundice, fever, and respiratory difficulty have been reported in association with disopyramide therapy, as have rare instances of thrombocytopenia, reversible agranulocytosis, and gynecomastia. Some cases of LE (lupus erythematosus) symptoms have been reported; most cases occurred in patients who had been switched to disopyramide from procainamide following the development of LE symptoms. Rarely, acute psychosis has been reported following Norpace therapy, with prompt return to normal mental status when therapy was stopped. The physician should be aware of these possible reactions and should discontinue Norpace or Norpace CR therapy promptly if they occur.

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