Etodolac

INDICATIONS AND USAGE Carefully consider the potential benefits and risks of etodolac tablets and other treatment options before deciding to use etodolac tablets. Use the lowest effective dose for the shortest duration consistent with individual patient treatment goals (see WARNINGS ). Etodolac tablets are indicated: For acute and long-term use in the management of signs and symptoms of the following: Osteoarthritis Rheumatoid arthritis For the management of acute pain

CLINICAL PHARMACOLOGY Pharmacodynamics Etodolac is a nonsteroidal anti-inflammatory drug (NSAID) that exhibits anti-inflammatory, analgesic, and antipyretic activities in animal models. The mechanism of action of etodolac, like that of other NSAIDs, is not completely understood, but may be related to the prostaglandin synthetase inhibition. Etodolac is a racemic mixture of [-]R- and [+]S-etodolac. As with other NSAIDs, it has been demonstrated in animals that the [+]S-form is biologically active. Both enantiomers are stable and there is no [-]R to [+]S conversion in vivo. Pharmacokinetics Absorption The systemic bioavailability of etodolac from etodolac tablet is 100% as compared to solution and at least 80% as determined from mass balance studies. Etodolac is well absorbed and had a relative bioavailability of 100% when 200 mg capsules were compared with a solution of etodolac. Based on mass balance studies, the systemic availability of etodolac from the tablet formulation is at least 80%. Etodolac does not undergo significant first-pass metabolism following oral administration. Mean (± 1 SD) peak plasma concentrations (C max ) range from approximately 14 ± 4 to 37 ± 9 mcg/mL after 200 to 600 mg single doses and are reached in 80 ± 30 minutes (see Table 1 for summary of pharmacokinetic parameters). The dose-proportionality based on the area under the plasma concentration-time curve (AUC) is linear following doses up to 600 mg every 12 hours. Peak concentrations are dose proportional for both total and free etodolac following doses up to 400 mg every 12 hours, but following a 600 mg dose, the peak is about 20% higher than predicted on the basis of lower doses. The extent of absorption of etodolac is not affected when etodolac tablets are administered after a meal. Food intake, however, reduces the peak concentration reached by approximately one-half and increases the time to peak concentration by 1.4 to 3.8 hours. Table 1. Mean (CV%) * Pharmacokinetic Parameters of Etodolac in Normal Healthy Adults and Various Special Populations PK Parameters Normal Healthy Adults (18 to 65) † Healthy Males (18 to 65) Healthy Females (27 to 65) Elderly (>65) (70 to 84) Hemodialysis (24 to 65) (n=9) Renal Impairment (46 to 73) Hepatic Impairment (34 to 60) (n=179) (n=176) (n=3) Dialysis On Dialysis Off (n=10) (n=9) T max , h 1.4 (61%) * 1.4 (60%) 1.7 (60%) 1.2 (43%) 1.7 (88%) 0.9 (67%) 2.1 (46%) 1.1 (15%) Oral Clearance, mL/h/kg (CL/F) 49.1 (33%) 49.4 (33%) 35.7 (28%) 45.7 (27%) NA NA 58.3 (19%) 42 (43%) Apparent Volume of Distribution, mL/kg (Vd/F) 393 (29%) 394 (29%) 300 (8%) 414 (38%) NA NA NA NA Terminal Half-Life, h 6.4 (22%) 6.4 (22%) 7.9 (35%) 6.5 (24%) 5.1 (22%) 7.5 (34%) NA 5.7 (24%) NA = not available * % Coefficient of variation † Age Range (years) Distribution The mean apparent volume of distribution (Vd/F) of etodolac is approximately 390 mL/kg. Etodolac is more than 99% bound to plasma proteins, primarily to albumin. The free fraction is less than 1

DOSAGE AND ADMINISTRATION Carefully consider the potential benefits and risks of etodolac tablets and other treatment options before deciding to use etodolac tablets. Use the lowest effective dose for the shortest duration consistent with individual patient treatment goals (see WARNINGS ). After observing the response to initial therapy with etodolac tablets, the dose and frequency should be adjusted to suit an individual patient's needs. Dosage adjustment of etodolac tablets is generally not required in patients with mild to moderate renal impairment. Etodolac should be used with caution in such patients, because, as with other NSAIDs, it may further decrease renal function in some patients with impaired renal function (see WARNINGS, Renal Effects ). Analgesia The recommended total daily dose of etodolac for acute pain is up to 1000 mg, given as 200 to 400 mg every 6 to 8 hours. Doses of etodolac greater than 1000 mg/day have not been adequately evaluated in well-controlled trials. Osteoarthritis and Rheumatoid Arthritis The recommended starting dose of etodolac for the management of the signs and symptoms of osteoarthritis or rheumatoid arthritis is: 300 mg b.i.d., t.i.d., or 400 mg b.i.d., or 500 mg b.i.d. A lower dose of 600 mg/day may suffice for long-term administration. Physicians should be aware that doses above 1000 mg/day have not been adequately evaluated in well-controlled clinical trials. In chronic conditions, a therapeutic response to therapy with etodolac is sometimes seen within one week of therapy, but most often is observed by two weeks. After a satisfactory response has been achieved, the patient's dose should be reviewed and adjusted as required.

ADVERSE REACTIONS In patients taking etodolac or other NSAIDs, the most frequently reported adverse experiences occurring in approximately 1 to 10% of patients are: Gastrointestinal experiences including: abdominal pain, constipation, diarrhea, dyspepsia, flatulence, gross bleeding/perforation, heartburn, nausea, GI ulcers (gastric/duodenal), vomiting. Other events including: abnormal renal function, anemia, dizziness, edema, elevated liver enzymes, headaches, increased bleeding time, pruritis, rashes, tinnitus. Adverse-reaction information for etodolac was derived from 2,629 arthritic patients treated with etodolac in double-blind and open-label clinical trials of 4 to 320 weeks in duration and worldwide postmarketing surveillance studies. In clinical trials, most adverse reactions were mild and transient. The discontinuation rate in controlled clinical trials, because of adverse events, was up to 10% for patients treated with etodolac. New patient complaints (with an incidence greater than or equal to 1%) are listed below by body system. The incidences were determined from clinical trials involving 465 patients with osteoarthritis treated with 300 to 500 mg of etodolac b.i.d. (i.e., 600 to 1000 mg/day). Incidence Greater Than Or Equal To 1% - Probably Causally Related Body as a whole - Chills and fever. Digestive system - Dyspepsia (10%), abdominal pain 1 , diarrhea 1 , flatulence 1 , nausea 1 , abdominal distension, epigastric pain, abnormal stools, constipation, gastritis, melena, vomiting. Nervous system - Asthenia/malaise 1 , dizziness 1 , depression, nervousness, fatigue. Skin and appendages - Pruritus, rash. Special senses - Blurred vision, tinnitus. Urogenital system - Dysuria, urinary frequency. Musculoskeletal—Arthralgia. 1 Drug-related patient complaints occurring in 3 to 9% of patients treated with etodolac. Drug-related patient complaints occurring in fewer than 3%, but more than 1%, are unmarked. Incidence Less Than 1% - Probably Causally Related (Adverse reactions reported only in worldwide postmarketing experience, not seen in clinical trials, are considered rarer and are italicized.) Body as a whole - Allergic reaction, anaphylactic/anaphylactoid reactions (including shock). Cardiovascular system - Hypertension, congestive heart failure, flushing, palpitations, syncope, vasculitis (including necrotizing and allergic). Digestive system - Thirst, dry mouth, ulcerative stomatitis, anorexia, eructation, elevated liver enzymes, cholestatic hepatitis, hepatitis, cholestatic jaundice, duodenitis, jaundice, hepatic failure, liver necrosis, peptic ulcer with or without bleeding and/or perforation, intestinal ulceration, pancreatitis. Hemic and lymphatic system - Ecchymosis, anemia, thrombocytopenia, bleeding time increased, agranulocytosis, hemolytic anemia, aplastic anemia, leukopenia, neutropenia, pancytopenia. Metabolic and nutritional - Edema, serum creatinine increase, hyperglycemia in previously controlled diabetic patients. Nervous system - Insomnia, somnolence. Respiratory system - Asthma, pulmonary infiltration with eosinophilia . Skin and appendages - Angioedema, sweating, urticaria, exfoliative dermatitis, vesiculobullous rash, cutaneous vasculitis with purpura, Stevens-Johnson Syndrome, toxic epidermal necrolysis, fixed drug eruption (FDE), leukocytoclastic vasculitis, hyperpigmentation , erythema multiforme. Special senses - Photophobia, transient visual disturbances. Urogenital system - Elevated BUN, renal failure, renal insufficiency, renal papillary necrosis. Incidence Less Than 1% - Causal Relationship Unknown (Medical events occurring under circumstances where causal relationship to etodolac is uncertain. These reactions are listed as alerting information for physicians.) Body as a whole - Infection, headache. Cardiovascular system - Arrhythmias, myocardial infarction, cerebrovascular accident. Digestive system - Esophagitis with or without stricture or cardiospasm, colitis, GI discomfort, burning se

WARNINGS CARDIOVASCULAR EFFECTS Cardiovascular Thrombotic Events Clinical trials of several COX-2 selective and nonselective NSAIDs of up to three years duration have shown an increased risk of serious cardiovascular (CV) thrombotic events, including myocardial infarction (MI) and stroke, which can be fatal. Based on available data, it is unclear that the risk for CV thrombotic events is similar for all NSAIDs. The relative increase in serious CV thrombotic events over baseline conferred by NSAID use appears to be similar in those with and without known CV disease or risk factors for CV disease. However, patients with known CV disease or risk factors had a higher absolute incidence of excess serious CV thrombotic events, due to their increased baseline rate. Some observational studies found that this increased risk of serious CV thrombotic events began as early as the first weeks of treatment. The increase in CV thrombotic risk has been observed most consistently at higher doses. To minimize the potential risk for an adverse CV event in NSAID-treated patients, use the lowest effective dose for the shortest duration possible. Physicians and patients should remain alert for the development of such events, throughout the entire treatment course, even in the absence of previous CV symptoms. Patients should be informed about the symptoms of serious CV events and the steps to take if they occur. There is no consistent evidence that concurrent use of aspirin mitigates the increased risk of serious CV thrombotic events associated with NSAID use. The concurrent use of aspirin and an NSAID, such as etodolac, increases the risk of serious gastrointestinal (GI) events (see WARNINGS ). Status Post Coronary Artery Bypass Graft (CABG) Surgery Two large, controlled clinical trials of a COX-2 selective NSAID for the treatment of pain in the first 10 to 14 days following CABG surgery found an increased incidence of myocardial infarction and stroke. NSAIDs are contraindicated in the setting of CABG (see CONTRAINDICATIONS ). Post-MI Patients Observational studies conducted in the Danish National Registry have demonstrated that patients treated with NSAIDs in the post-MI period were at increased risk of reinfarction, CV-related death, and all-cause mortality beginning in the first week of treatment. In this same cohort, the incidence of death in the first year post MI was 20 per 100 person years in NSAID-treated patients compared to 12 per 100 person years in non-NSAID exposed patients. Although the absolute rate of death declined somewhat after the first year post-MI, the increased relative risk of death in NSAID users persisted over at least the next four years of follow-up. Avoid the use of etodolac in patients with a recent MI unless the benefits are expected to outweigh the risk of recurrent CV thrombotic events. If etodolac is used in patients with a recent MI, monitor patients for signs of cardiac ischemia. Hypertension NSAIDs, including etodolac, can lead to onset of new hypertension or worsening of pre-existing hypertension, either of which may contribute to the increased incidence of CV events. Patients taking thiazides or loop diuretics may have impaired response to these therapies when taking NSAIDs. NSAIDs, including etodolac, should be used with caution in patients with hypertension. Blood pressure (BP) should be monitored closely during the initiation of NSAID treatment and throughout the course of therapy. Heart Failure and Edema The Coxib and traditional NSAID Trialists' Collaboration meta-analysis of randomized controlled trials demonstrated an approximately two-fold increase in hospitalizations for heart failure in COX-2 selective-treated patients and nonselective NSAID-treated patients compared to placebo-treated patients. In a Danish National Registry study of patients with heart failure, NSAID use increased the risk of MI, hospitalization for heart failure, and death. Additionally, fluid retention and edema have been observed

CONTRAINDICATIONS Etodolac tablets are contraindicated in patients with known hypersensitivity to etodolac or other ingredients in etodolac tablets. Etodolac tablets should not be given to patients who have experienced asthma, urticaria, or other allergic-type reactions after taking aspirin or other NSAIDs. Severe, rarely fatal, anaphylactic-like reactions to NSAIDs have been reported in such patients (see WARNINGS, Anaphylactoid Reactions and PRECAUTIONS, Pre-existing Asthma ). In the setting of coronary artery bypass graft (CABG) surgery (see WARNINGS ).

OVERDOSAGE Symptoms following acute NSAID overdose are usually limited to lethargy, drowsiness, nausea, vomiting, and epigastric pain, which are generally reversible with supportive care. Gastrointestinal bleeding can occur and coma has occurred following massive ibuprofen or mefenamic-acid overdose. Hypertension, acute renal failure, and respiratory depression may occur but are rare. Anaphylactoid reactions have been reported with therapeutic ingestion of NSAIDs, and may occur following overdose. Patients should be managed by symptomatic and supportive care following an NSAID overdose. There are no specific antidotes. Emesis and/or activated charcoal (60 to 100 g in adults, 1 to 2 g/kg in children) and/or osmotic cathartic may be indicated in patients seen within 4 hours of ingestion with symptoms or following a large overdose (5 to 10 times the usual dose). Forced diuresis, alkalinization of the urine, hemodialysis, or hemoperfusion would probably not be useful due to etodolac's high protein binding.