DICLOFENAC SODIUM

Drug Interactions See Table 2 for clinically significant drug interactions with diclofenac. Table 2: Clinically Significant Drug Interactions with Diclofenac Drugs That Interfere with Hemostasis Clinical Impact: Diclofenac and anticoagulants such as warfarin have a synergistic effect on bleeding. The concomitant use of diclofenac 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 diclofenac 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 PRECAUTIONS ; Hematological Toxicity ). Aspirin Clinical Impact: 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; Gastrointestinal Bleeding, Ulceration, and Perforation ) . Intervention: Concomitant use of diclofenac and analgesic doses of aspirin is not generally recommended because of the increased risk of bleeding ( see PRECAUTIONS: Hematological Toxicity ). Diclofenac is not a substitute 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 diclofenac and ACE-inhibitors, ARBs, or betablockers, monitor blood pressure to ensure that the desired blood pressure is obtained. During concomitant use of diclofenac 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; Renal Toxicity and Hyperkalemia ). 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 diclofenac with diuretics, observe patients for signs of worsening renal function, in addition to assuring diuretic efficacy including antihypertensive effects ( see WARNINGS; Renal Toxicity and Hyperkalemia ). Digoxin Clinical Impact: The concomitant use of diclofenac with digoxin has been reported to increase the serum concentration and prolong the half-life of digoxin. Intervention: During concomitant use of diclofenac and digoxin, monitor serum digoxin levels. Lithium Clinical Impact: NSAIDs have produced elevations in plasma lithium levels and reductions in renal lithium clearance. The mean minimum lithium concentration increased 15%, and the renal clearance decreased by approximately 20%. This effect has been attributed to NSAID inhibition of renal prostaglandin synthesis. Intervention: During concomitant use of diclofenac and lithium, monitor patients for signs of lithium toxicity. Methotrexate Clinical Impact: Concomitant use of NSAIDs and methotrexate may increase the risk for methotrexate toxicity (e.g., neutropenia, thrombocytopenia, renal dysfunction). Intervention: During concomitant use of diclofenac and methotrexate, monitor patients for methotrexate toxicity. Cyclosporine Clinical Impact: Concomitant use of diclofenac and cyclosporine may increase cyclosporine's nephrotoxicity. Intervention: During concomitant use of diclofenac and cyclosporine, monitor patients for signs of worsening renal function. NSAIDs and Salicylates Clinical Impact: Concomitant use of diclofenac with other NSAIDs or salicylates (e.g., diflunisal, salsalate) increases the risk of GI toxicity, with little or no increase in efficacy ( see WARNINGS; Gastrointestinal Bleeding, Ulceration, and Perforation ). Intervention: The concomitant use of diclofenac with other NSAIDs or salicylates is not recommended. Pemetrexed Clinical Impact: Concomitant use of diclofenac and pemetrexed may increase the risk of pemetrexedassociated myelosuppression, renal, and GI toxicity (see the pemetrexed prescribing information). Intervention: During concomitant use of diclofenac and pemetrexed, in patients with renal impairment whose creatinine clearance ranges from 45 to 79 mL/min, monitor for myelosuppression, renal and GI toxicity. NSAIDs with short elimination half-lives (e.g., diclofenac, indomethacin) should be avoided for a period of two days before, the day of, and two days following administration of pemetrexed. In the absence of data regarding potential interaction between pemetrexed and NSAIDs with longer half-lives (e.g., meloxicam, nabumetone), patients taking these NSAIDs should interrupt dosing for at least five days before, the day of, and two days following pemetrexed administration. CYP2C9 Inhibitors or Inducers: Clinical Impact: Diclofenac is metabolized by cytochrome P450 enzymes, predominantly by CYP2C9. Co-administration of diclofenac with CYP2C9 inhibitors (e.g. voriconazole) may enhance the exposure and toxicity of diclofenac whereas co-administration with CYP2C9 inducers (e.g. rifampin) may lead to compromised efficacy of diclofenac. Intervention: A dosage adjustment may be warranted when diclofenac is administered with CYP2C9 inhibitors or inducers ( see CLINICAL PHARMACOLOGY; Pharmacokinetics ).

INDICATIONS AND USAGE Diclofenac sodium ophthalmic solution is indicated for the treatment of postoperative inflammation in patients who have undergone cataract extraction and for the temporary relief of pain and photophobia in patients undergoing corneal refractive surgery.

DOSAGE AND ADMINISTRATION Carefully consider the potential benefits and risks of diclofenac sodium delayed-release tablets and other treatment options before deciding to use diclofenac. Use the lowest effective dose for the shortest duration consistent with individual patient treatment goals (see WARNINGS; Gastrointestinal Bleeding, Ulceration, and Perforation ) . After observing the response to initial therapy with diclofenac, the dose and frequency should be adjusted to suit an individual patient's needs. For the relief of osteoarthritis, the recommended dosage is 100-150 mg/day in divided doses (50 mg twice a day or three times a day, or 75 mg twice a day). For the relief of rheumatoid arthritis, the recommended dosage is 150-200 mg/day in divided doses (50 mg three times a day. or four times a day, or 75 mg twice a day.). For the relief of ankylosing spondylitis, the recommended dosage is 100-125 mg/day, administered as 25 mg four times a day, with an extra 25-mg dose at bedtime if necessary.

ADVERSE REACTIONS Ocular Transient burning and stinging were reported in approximately 15% of patients across studies with the use of diclofenac sodium ophthalmic solution. In cataract surgery studies, keratitis was reported in up to 28% of patients receiving diclofenac sodium ophthalmic solution, although in many of these cases keratitis was initially noted prior to the initiation of treatment. Elevated intraocular pressure following cataract surgery was reported in approximately 15% of patients undergoing cataract surgery. Lacrimation complaints were reported in approximately 30% of case studies undergoing incisional refractive surgery. The following adverse reactions were reported in approximately 10% or less of the patients: abnormal vision, acute elevated IOP, blurred vision, conjunctivitis, corneal deposits, corneal edema, corneal opacity, corneal lesions, discharge, eyelid swelling, eye pain, injection (redness), iritis, irritation, itching, lacrimation disorder, and ocular allergy. Systemic The following adverse reactions were reported in 3% or less of the patients: abdominal pain, asthenia, chills, dizziness, facial edema, fever, headache, insomnia, nausea, pain, rhinitis, viral infection, and vomiting. Clinical Practice The following reactions have been identified during postmarketing use of topical diclofenac sodium ophthalmic solution, 0.1% in clinical practice. Because they are reported voluntarily from a population of unknown size, estimates of frequency cannot be made. The reactions, which have been chosen for inclusion due to either their seriousness, frequency of reporting, possible causal connection to topical diclofenac sodium ophthalmic solution, 0.1%, or a combination of these factors, include corneal erosion, corneal infiltrates, corneal perforation, corneal thinning, corneal ulceration, and epithelial breakdown (see PRECAUTIONS, General ). To report SUSPECTED ADVERSE REACTIONS, contact Bausch & Lomb Incorporated at 1-800-553-5340 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.