Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.
As with all drugs in this class, the frequency and severity of adverse events depends on several factors: the dose of the drug and duration of treatment; the age, the sex, physical condition of the patient; any concurrent medical diagnoses or individual risk factors. The following adverse reactions are divided into three parts based on frequency and whether or not the possibility exists of a causal relationship between drug usage and these adverse events. In those reactions listed as "Probable Causal Relationship" there is at least one case for each adverse reaction where there is evidence to suggest that there is a causal relationship between drug usage and the reported event. The adverse reactions reported were based on the results from two double-blind controlled clinical trials of three months duration with an additional nine month open-label extension. A total of 542 patients received naproxen sodium extended-release tablets either in the double-blind period or in the nine month open-label extension. Of these 542 patients, 232 received naproxen sodium extended-release tablets, 167 were initially treated with Naprosyn® and 143 were initially treated with placebo. Adverse reactions reported by patients who received naproxen sodium extended-release tablets are shown by body system. Those adverse reactions observed with naproxen but not reported in controlled trials with naproxen sodium extended-release tablets are italicized.
The most frequent adverse events from the double-blind and open-label clinical trials were headache (15%), followed by dyspepsia (14%), and flu syndrome (10%). The incidence of other adverse events occurring in 3% to 9% of the patients are marked with an asterisk.
Those reactions occurring in less than 3% of the patients are unmarked.
Incidence greater than 1% (probable causal relationship)
Body as a Whole -- Pain (back)*, pain*, infection*, fever, injury (accident), asthenia, pain chest, headache (15%), flu syndrome (10%).
Gastrointestinal -- Nausea*, diarrhea*, constipation*, abdominal pain*, flatulence, gastritis, vomiting, dysphagia, dyspepsia (14%), heartburn*, stomatitis.
Hematologic -- Anemia, ecchymosis.
Respiratory -- Pharyngitis*, rhinitis*, sinusitis*, bronchitis, cough increased.
Metabolic and Nutrition -- Peripheral edema, hyperglycemia.
Musculoskeletal -- Cramps (leg), myalgia, arthralgia, joint disorder, tendon disorder.
Incidence less than 1% (probable causal relationship)
Body as a Whole -- Abscess, monilia, neck rigid, pain neck, abdomen enlarged, carcinoma, cellulitis, edema general, LE syndrome, malaise, mucous membrane disorder, allergic reaction, pain pelvic.
Gastrointestinal -- Anorexia, cholecystitis, cholelithiasis, eructation, GI hemorrhage, rectal hemorrhage, stomatitis aphthous, stomatitis ulcer, ulcer mouth, ulcer stomach, periodontal abscess, cardiospasm, colitis, esophagitis, gastroenteritis, GI disorder, rectal disorder, tooth disorder, hepatosplenomegaly, liver function abnormality, melena, ulcer esophagus, hematemesis, jaundice, pancreatitis, necrosis.
Renal -- Dysmenorrhea, dysuria, kidney function abnormality, nocturia, prostate disorder, pyelonephritis, carcinoma breast, urinary incontinence, kidney calculus, kidney failure, menorrhagia, metrorrhagia, neoplasm breast, nephrosclerosis, hematuria, pain kidney, pyuria, urine abnormal, urinary frequency, urinary retention, uterine spasm, vaginitis, glomerular nephritis, hyperkalemia, interstitial nephritis, nephrotic syndrome, renal disease, renal failure, renal papillary necrosis.
Hematologic -- Leukopenia, bleeding time increased, eosinophilia, abnormal RBC, abnormal WBC, thrombocytopenia, agranulocytosis, granulocytopenia.
Central Nervous System -- Depression, anxiety, hypertonia, nervousness, neuralgia, neuritis, vertigo, amnesia, confusion, co-ordination, abnormal diplopia, emotional lability, hematoma subdural, paralysis, dream abnormalities, inability to concentrate, muscle weakness.
Dermatologic: Angiodermatitis, herpes simplex, dry skin, sweating, ulcer skin, acne, alopecia, dermatitis contact, eczema, herpes zoster, nail disorder, skin necrosis, subcutaneous nodule, pruritus, urticaria, neoplasm skin, photosensitive dermatitis, photosensitivity reactions resembling porphyria cutaneous tarda, epidermolysis bullosa.
Special Senses -- Amblyopia, scleritis, cataract, conjunctivitis, deaf, ear disorder, keratoconjunctivitis, lacrimation disorder, otitis media, pain eye.
Cardiovascular -- Angina pectoris, coronary artery disease, myocardial infarction, deep thrombophlebitis, vasodilation, vascular anomaly, arrhythmia, bundle branch block, abnormal ECG, heart failure right, hemorrhage, migraine, aortic stenosis, syncope, tachycardia, congestive heart failure.
Respiratory -- Asthma, dyspnea, lung edema, laryngitis, lung disorder, epistaxis, pneumonia, respiratory distress, respiratory disorder, eosinophilic pneumonitis.
Musculoskeletal -- Myasthenia, bone disorder, spontaneous bone fracture, fibrotendinitis, bone pain, ptosis, spasm general, bursitis.
Metabolic and Nutrition -- Creatinine increase, glucosuria, hypercholesteremia, albuminuria, alkalosis, BUN increased, dehydration, edema, glucose tolerance decrease, hyperuricemia, hypokalemia, SGOT increase, SGPT increase, weight decrease.
General -- Anaphylactoid reactions, angioneurotic edema, menstrual disorders, hypoglycemia, pyrexia (chills and fevers).
Incidence less than 1% (causal relationship unknown)
Other adverse reactions listed in the naproxen package label, but not reported by those who received naproxen sodium extended-release tablets are shown in italics. These observations are being listed as alerting information to the physician.