Naproxen

12.1 Mechanism of Action Naproxen has analgesic, anti-inflammatory, and antipyretic properties. Naproxen sodium has been developed as a more rapidly absorbed formulation of naproxen for use as an analgesic. The mechanism of action of naproxen, like that of other NSAIDs, is not completely understood but involves inhibition of cyclooxygenase (COX-1 and COX-2). Naproxen is a potent inhibitor of prostaglandin synthesis in vitro. Naproxen concentrations reached during therapy have produced in vivo effects. Prostaglandins sensitize afferent nerves and potentiate the action of bradykinin in inducing pain in animal models. Prostaglandins are mediators of inflammation. Because naproxen is an inhibitor of prostaglandin synthesis, its mode of action may be due to a decrease of prostaglandins in peripheral tissues.

1 INDICATIONS AND USAGE Naproxen tablets and naproxen sodium tablets are indicated for: the relief of the signs and symptoms of: • rheumatoid arthritis • osteoarthritis • ankylosing spondylitis • Polyarticular Juvenile Idiopathic Arthritis Naproxen tablets and naproxen sodium tablets are also indicated for: the relief of signs and symptoms of: • tendonitis • bursitis • acute gout the management of: • pain • primary dysmenorrhea Naproxen tablets and naproxen sodium tablets are non-steroidal anti-inflammatory drugs indicated for: the relief of the signs and symptoms of: • rheumatoid arthritis • osteoarthritis • ankylosing spondylitis • polyarticular juvenile idiopathic arthritis Naproxen tablets and naproxen sodium tablets are also indicated for: the relief of signs and symptoms of: • tendonitis • bursitis • acute gout the management of: • pain • primary dysmenorrhea

2 DOSAGE AND ADMINISTRATION Use the lowest effective dosage for shortest duration consistent with individual patient treatment goals. ( 2.1 ) Rheumatoid Arthritis, Osteoarthritis, and Ankylosing Spondylitis Naproxen tablets 250 mg (one-half tablet) 500 mg twice daily Naproxen sodium tablets 275 mg (one-half tablet) 550 mg twice daily The dose may be adjusted up or down depending on the clinical response of the patient. In patients who tolerate lower doses well, the dose may be increased to naproxen 1500 mg/ day for up to 6 months. Polyarticular Juvenile Idiopathic Arthritis Naproxen tablets may not allow for the flexible dose titration needed in pediatric patients with polyarticular juvenile idiopathic arthritis. A liquid formulation may be more appropriate. Recommended total daily dose of naproxen is approximately 10 mg/kg given in 2 divided doses. Dosing with naproxen tablets is not appropriate for children weighing less than 50 kilograms. Management of Pain, Primary Dysmenorrhea, and Acute Tendonitis and Bursitis Recommended starting dose 550 mg of naproxen sodium as naproxen sodium tablets followed by 550 mg every 12 hours or 275 mg every 6 to 8 hours as required. The initial total daily dose should not exceed 1375 mg of naproxen sodium. Thereafter, the total daily dose should not exceed 1100 mg of naproxen sodium. Naproxen sodium tablets are recommended for the management of acute painful conditions when prompt onset of pain relief is desired. Acute Gout Recommended starting dose 750 mg of naproxen tablets followed by 250 mg every 8 hours until the attack has subsided. Naproxen sodium tablets may also be used at a starting dose of 825 mg followed by 275 mg every 8 hours. 2.1 General Dosing Instructions Carefully consider the potential benefits and risks of naproxen tablets and naproxen sodium tablets and other treatment options before deciding to use naproxen tablets and naproxen sodium tablets. Use the lowest effective dose for the shortest duration consistent with individual patient treatment goals [ see Warnings and Precautions ( 5 ) ]. After observing the response to initial therapy with naproxen tablets or naproxen sodium tablets, the dose and frequency should be adjusted to suit an individual patient’s needs. Naproxen-containing products such as naproxen and naproxen sodium tablets, and other naproxen products should not be used concomitantly since they all circulate in the plasma as the naproxen anion. 2.2 Rheumatoid Arthritis, Osteoarthritis and Ankylosing Spondylitis The recommended dosages of naproxen tablets and naproxen sodium tablets are shown in Table 1. Table 1: Recommended dosages for naproxen tablets and naproxen sodium tablets Naproxen tablets 250 mg (one half tablet) 500 mg twice daily Naproxen sodium tablets 275 mg (one half tablet) 550 mg (naproxen 500 mg with 50 mg sodium) twice daily During long-term administration, the dose of naproxen may be adjusted up or down depending on the clinical response of the patient. A lower daily dose may suffice for long-term administration. The morning and evening doses do not have to be equal in size and administration of the drug more frequently than twice daily does not generally make a difference in response. In patients who tolerate lower doses well, the dose may be increased to naproxen 1500 mg/day for limited periods of up to 6 months when a higher level of anti-inflammatory/analgesic activity is required. When treating such patients with naproxen 1500 mg/day, the physician should observe sufficient increased clinical benefits to offset the potential increased risk. 2.3 Polyarticular Juvenile Idiopathic Arthritis Naproxen solid-oral dosage forms may not allow for the flexible dose titration needed in pediatric patients with polyarticular juvenile idiopathic arthritis. A liquid formulation may be more appropriate for weight-based dosing and due to the need for dose flexibility in children. In pediatric patients, doses of 5 mg/kg/day produced plasma levels of naproxen similar to those seen in adults taking 500 mg of naproxen [ see Clinical Pharmacology ( 12 ) ]. The recommended total daily dose of naproxen is approximately 10 mg/kg given in 2 divided doses. Dosing with naproxen tablets is not appropriate for children weighing less than 50 kilograms. 2.4 Management of Pain, Primary Dysmenorrhea, and Acute Tendonitis and Bursitis The recommended starting dose of naproxen sodium tablets is 550 mg followed by 550 mg every 12 hours or 275 mg (one half of a 550 mg tablet) every 6 to 8 hours as required. The initial total daily dose should not exceed 1375 mg (two and one-half tablets) of naproxen sodium. Thereafter, the total daily dose should not exceed 1100 mg of naproxen sodium. Because the sodium salt of naproxen is more rapidly absorbed, naproxen sodium tablets is recommended for the management of acute painful conditions when prompt onset of pain relief is desired. Naproxen tablets may also be used. The recommended starting dose of naproxen ta

6 ADVERSE REACTIONS The following adverse reactions are discussed in greater detail in other sections of the labeling: • Cardiovascular Thrombotic Events [ see Warnings and Precautions ( 5.1 ) ] • GI Bleeding, Ulceration, and Perforation [ see Warnings and Precautions ( 5.2 ) ] • Hepatotoxicity [ see Warnings and Precautions ( 5.3 ) ] • Hypertension [ see Warnings and Precautions ( 5.4 ) ] • Heart Failure and Edema [ see Warnings and Precautions ( 5.5 ) ] • Renal Toxicity and Hyperkalemia [ see Warnings and Precautions ( 5.6 ) ] • Anaphylactic Reactions [ see Warnings and Precautions ( 5.7 ) ] • Serious Skin Reactions [ see Warnings and Precautions ( 5.9 ) ] • Hematologic Toxicity [ see Warnings and Precautions ( 5.12 ) ] Most common adverse reactions to naproxen were dyspepsia, abdominal pain, nausea, headache, rash, ecchymosis, and edema. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Glenmark Pharmaceuticals Inc., USA at 1 (888) 721-7115 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience 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. Adverse reactions reported in controlled clinical trials in 960 patients treated for rheumatoid arthritis or osteoarthritis are listed below. In general, reactions in patients treated chronically were reported 2 to 10 times more frequently than they were in short-term studies in the 962 patients treated for mild to moderate pain or for dysmenorrhea. The most frequent complaints reported related to the gastrointestinal tract. A clinical study found gastrointestinal reactions to be more frequent and more severe in rheumatoid arthritis patients taking daily doses of 1500 mg naproxen compared to those taking 750 mg naproxen. In controlled clinical trials with about 80 pediatric patients and in well-monitored, open-label studies with about 400 pediatric patients with polyarticular juvenile idiopathic arthritis treated with naproxen, the incidence of rash and prolonged bleeding times were greater, the incidence of gastrointestinal and central nervous system reactions were about the same, and the incidence of other reactions were lower in pediatric patients than in adults. In patients taking naproxen in clinical trials, the most frequently reported adverse experiences in approximately 1% to 10% of patients were: Gastrointestinal (GI) Experiences, including: heartburn*, abdominal pain*, nausea*, constipation*, diarrhea, dyspepsia, stomatitis Central Nervous System: headache*, dizziness*, drowsiness*, lightheadedness, vertigo Dermatologic: pruritus (itching)*, skin eruptions*, ecchymoses*, sweating, purpura Special Senses: tinnitus*, visual disturbances, hearing disturbances Cardiovascular: edema*, palpitations General: dyspnea*, thirst *Incidence of reported reaction between 3% and 9%. Those reactions occurring in less than 3% of the patients are unmarked. In patients taking NSAIDs, the following adverse experiences have also been reported in approximately 1% to 10% of patients. Gastrointestinal (GI) Experiences, including: flatulence, gross bleeding/perforation, GI ulcers (gastric/duodenal), vomiting General: abnormal renal function, anemia, elevated liver enzymes, increased bleeding time, rashes The following are additional adverse experiences reported in <1% of patients taking naproxen during clinical trials. Gastrointestinal: pancreatitis, vomiting Hepatobiliary: jaundice Hemic and Lymphatic: melena, thrombocytopenia, agranulocytosis Nervous System: inability to concentrate Dermatologic: skin rashes 6.2 Postmarketing Experience The following adverse reactions have been identified during post approval use of naproxen. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. The following are additional adverse experiences reported in <1% of patients taking naproxen during clinical trials and through postmarketing reports. Those adverse reactions observed through postmarketing reports are italicized. Body as a Whole: anaphylactoid reactions, angioneurotic edema, menstrual disorders, pyrexia (chills and fever) Cardiovascular: congestive heart failure, vasculitis, hypertension, pulmonary edema Gastrointestinal: inflammation, bleeding (sometimes fatal, particularly in the elderly), ulceration, perforation and obstruction of the upper or lower gastrointestinal tract. Esophagitis, stomatitis, hematemesis, colitis, exacerbation of inflammatory bowel disease (ulcerative colitis, Crohn’s disease). Hepatobiliary: abnormal liver function tests, hepatitis (some cases have been fatal) Hemic and Lymphatic: eosinophilia, leucopenia, granulocytopenia, hemolytic anemia, aplastic anemia Metabolic and Nutr

7 DRUG INTERACTIONS See Table 1 for clinically significant drug interactions with naproxen. Table 1: Clinically Significant Drug Interactions with naproxen Drugs That Interfere with Hemostasis Clinical Impact: • Naproxen and anticoagulants such as warfarin have a synergistic effect on bleeding. The concomitant use of naproxen and anticoagulants have an increased risk of serious bleeding compared to the use of either drug alone. • Serotonin release by platelets plays an important role in hemostasis. Case-control and cohort epidemiological studies showed that concomitant use of drugs that interfere with serotonin reuptake and an NSAID may potentiate the risk of bleeding more than an NSAID alone. Intervention: Monitor patients with concomitant use of naproxen tablets or naproxen sodium tablets with anticoagulants (e.g., warfarin), antiplatelet agents (e.g., aspirin), selective serotonin reuptake inhibitors (SSRIs), and serotonin norepinephrine reuptake inhibitors (SNRIs) for signs of bleeding [ see Warnings and Precautions ( 5.12 ) ]. Aspirin Clinical Impact: A pharmacodynamic (PD) study has demonstrated an interaction in which lower dose naproxen (220mg/day or 220mg twice daily) interfered with the antiplatelet effect of low-dose immediate-release aspirin, with the interaction most marked during the washout period of naproxen ( see 12.2 Pharmacodynamics) . There is reason to expect that the interaction would be present with prescription doses of naproxen or with enteric-coated low-dose aspirin; however, the peak interference with aspirin function may be later than observed in the PD study due to the longer washout period. Controlled clinical studies showed that the concomitant use of NSAIDs and analgesic doses of aspirin does not produce any greater therapeutic effect than the use of NSAIDs alone. In a clinical study, the concomitant use of an NSAID and aspirin was associated with a significantly increased incidence of GI adverse reactions as compared to use of the NSAID alone [ see Warnings and Precautions ( 5.2 ) ]. Intervention: Because there may be an increased risk of cardiovascular events following discontinuation of naproxen due to the interference with the antiplatelet effect of aspirin during the washout period, for patients taking low-dose aspirin for cardioprotection who require intermittent analgesics, consider use of an NSAID that does not interfere with the antiplatelet effect of aspirin, or non-NSAID analgesics where appropriate. Concomitant use of naproxen tablets or naproxen sodium tablets and analgesic doses of aspirin is not generally recommended because of the increased risk of bleeding [ see Warnings and Precautions ( 5.12 ) ]. Naproxen tablets or naproxen sodium tablets are not substitutes for low dose aspirin for cardiovascular protection. ACE Inhibitors, Angiotensin Receptor Blockers, and Beta-Blockers Clinical Impact: • NSAIDs may diminish the antihypertensive effect of angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), or beta-blockers (including propranolol). • In patients who are elderly, volume-depleted (including those on diuretic therapy), or have renal impairment, co-administration of an NSAID with ACE inhibitors or ARBs may result in deterioration of renal function, including possible acute renal failure. These effects are usually reversible. Intervention: • During concomitant use of naproxen tablets or naproxen sodium tablets and ACE-inhibitors, ARBs, or beta-blockers, monitor blood pressure to ensure that the desired blood pressure is obtained. • During concomitant use of naproxen tablets or naproxen sodium tablets and ACE-inhibitors or ARBs in patients who are elderly, volume-depleted, or have impaired renal function, monitor for signs of worsening renal function [ see Warnings and Precautions ( 5.6 ) ]. • When these drugs are administered concomitantly, patients should be adequately hydrated. Assess renal function at the beginning of the concomitant treatment and periodically thereafter. Diuretics Clinical Impact: Clinical studies, as well as post-marketing observations, showed that NSAIDs reduced the natriuretic effect of loop diuretics (e.g., furosemide) and thiazide diuretics in some patients. This effect has been attributed to the NSAID inhibition of renal prostaglandin synthesis. Intervention: During concomitant use of naproxen tablets or naproxen sodium tablets with diuretics, observe patients for signs of worsening renal function, in addition to assuring diuretic efficacy including antihypertensive effects [ see Warnings and Precautions ( 5.6 ) ]. Digoxin Clinical Impact: The concomitant use of naproxen with digoxin has been reported to increase the serum concentration and prolong the half-life of digoxin. Intervention: During concomitant use of naproxen tablets or naproxen sodium tablets and digoxin, monitor serum digoxin levels. Lithium Clinical Impact: NSAIDs have produced elevations in plasma lithium levels and reductions in re