Diclofenac

Diclofenac sodium topical solution is a nonsteroidal anti-inflammatory drug indicated for the treatment of the pain of osteoarthritis of the knee(s). Diclofenac sodium topical solution is indicated for the treatment of the pain of osteoarthritis of the knee(s).

Use the lowest effective dosage for the shortest duration consistent with individual patient treatment goals. The recommended dose is 2 pump actuations on each painful knee, 2 times a day. Apply diclofenac sodium topical solution, to clean, dry skin. Dispense 40 mg (2 pump actuations) directly onto the knee or first into the hand and then onto the knee. Spread evenly around front, back and sides of the knee. Wash hands completely after administering the product. Wait until the area is completely dry before covering with clothing or applying sunscreen, insect repellent, cosmetics, topical medications, or other substances. Until the treated knee(s) is completely dry, avoid skin-to-skin contact between other people and the treated knee(s). Do not get diclofenac sodium topical solution in your eyes, nose, or mouth.

2.1General Dosing Instructions Use the

lowest effective dosage for the shortest duration consistent with individual patient treatment goals . For relief of the pain of osteoarthritis (OA) of the knee(s), the recommended dose is 40 mg of diclofenac sodium (2 pump actuations) on each painful knee, 2 times a day. Apply diclofenac sodium topical solution to clean, dry skin. The pump must be primed before first use.

Instruct patients to fully depress the pump mechanism (actuation) 4 times while holding the bottle in an upright position. This portion should be discarded to ensure proper priming of the pump. No further priming of the bottle should be required. After the priming procedure, diclofenac sodium topical solution is properly dispensed by completely depressing the pump 2 times to achieve the prescribed dosage for one knee.

Deliver the product directly into the palm of the hand and then apply evenly around front, back, and sides of the knee. Application of diclofenac sodium topical solution in an amount exceeding or less than the recommended dose has not been studied and is therefore not recommended.

2.2Special Precautions Avoid

showering/bathing for at least 30 minutes after the application of diclofenac sodium topical solution to the treated knee. Wash and dry hands after use. Do not apply diclofenac sodium topical solution to open wounds. Avoid contact of diclofenac sodium topical solution with eyes and mucous membranes.

Do not apply external heat and/or occlusive dressings to treated knees. Avoid wearing clothing over the diclofenac sodium topical solution-treated knee(s) until the treated knee is dry. Protect the treated knee(s) from natural and artificial sunlight. Wait until the treated area is dry before applying sunscreen, insect repellant, lotion, moisturizer, cosmetics, or other topical medication to the same knee you have just treated with diclofenac sodium topical solution.

Until the treated knee(s) is completely dry, avoid skin-to-skin contact between other people and the treated knee(s). Do not use combination therapy with diclofenac sodium topical solution and an oral NSAID unless the benefit outweighs the risk and conduct periodic laboratory evaluations.

Hepatotoxicity : Inform patients of warning signs and symptoms of hepatotoxicity. Discontinue if abnormal liver tests persist or worsen or if clinical signs and symptoms of liver disease develop Hypertension : Patients taking some antihypertensive medications may have impaired response to these therapies when taking NSAIDs. Monitor blood pressure ( 5.4 , 7 ) Heart Failure and Edema : Avoid use of diclofenac sodium topical solution in patients with severe heart failure unless benefits are expected to outweigh risk of worsening heart failure Renal Toxicity: Monitor renal function in patients with renal or hepatic impairment, heart failure, dehydration, or hypovolemia. Avoid use of diclofenac sodium topical solution in patients with advanced renal disease unless benefits are expected to outweigh risk of worsening renal function Anaphylactic Reactions : Seek emergency help if an anaphylactic reaction occurs Exacerbation of Asthma Related to Aspirin Sensitivity : Diclofenac sodium topical solution is contraindicated in patients with aspirin-sensitive asthma. Monitor patients with preexisting asthma (without aspirin sensitivity) Serious Skin Reactions : Discontinue diclofenac sodium topical solution at first appearance of skin rash or other signs of hypersensitivity. ( 5.9 , 5.15 ) Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS): Discontinue and evaluate clinically Fetal Toxicity : Limit use of NSAIDs, including diclofenac sodium topical solution, between about 20 to 30 weeks in pregnancy due to the risk of oligohydramnios/fetal renal dysfunction. Avoid use of NSAIDs in women at about 30 weeks gestation and later in pregnancy due to the risks of oligohydramnios/fetal renal dysfunction and premature closure of the fetal ductus arteriosus ( 5.11 , 8.1 ). Hematologic Toxicity : Monitor hemoglobin or hematocrit in patients with any signs or symptoms of anemia ( 5.12 , 7 ). Exposure to light : Avoid exposure of treated knee(s) to natural or artificial sunlight. Eye Contact : Avoid contact of diclofenac sodium topical solution with eyes and mucosa. Oral Nonsteroidal Anti-inflammatory Drugs : Avoid concurrent use with oral NSAIDs. )

5.1Cardiovascular 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 diclofenac, increases the risk of serious gastrointestinal (GI) events . 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 . 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 diclofenac sodium topical solution in patients with a recent MI unless the benefits are expected to outweigh the risk of recurrent CV thrombotic events.

If diclofenac sodium topical solution is used in patients with a recent MI, monitor patients for signs of cardiac ischemia.

5.2Gastrointestinal Bleeding, Ulceration, and Perforation NSAIDs,

including diclofenac, cause serious gastrointestinal (GI) adverse events including inflammation, bleeding, ulceration, and perforation of the esophagus, stomach, small intestine, or large intestine, which can be fatal. These serious adverse events can occur at any time, with or without warning symptoms, in patients treated with NSAIDs. Only one in five patients who develop a serious upper GI adverse event on NSAID therapy is symptomatic.

Upper GI ulcers, gross bleeding, or perforation caused by NSAIDs occurred in approximately 1% of patients treated for 3 to 6 months, and in about 2% to 4% of patients treated for one year. However, even short-term NSAID therapy is not without risk. Risk Factors for GI Bleeding, Ulceration, and Perforation Patients with a prior history of peptic ulcer disease and/or GI bleeding who used NSAIDs had a greater than 10-fold increased risk for developing a GI bleed compared to patients without these risk factors.

Other factors that increase the risk of GI bleeding in patients treated with NSAIDs include longer duration of NSAID therapy; concomitant use of oral corticosteroids, aspirin, anticoagulants, or selective serotonin reuptake inhibitors (SSRIs); smoking; use of alcohol; older age; and poor general health status. Most postmarketing reports of fatal GI events occurred in elderly or debilitated patients. Additionally, patients with advanced liver disease and/or coagulopathy are at increased risk for GI bleeding.

Strategies to Minimize the GI Risks in NSAID-treated patients Use the lowest effective dosage for the shortest possible duration. Avoid administration of more than one NSAID at a time. Avoid use in patients at higher risk unless benefits are expected to outweigh the increased risk of bleeding.

For such patients, as well as those with active GI bleeding, consider alternate therapies other than NSAIDs. Remain alert for signs and symptoms of GI ulceration and bleeding during NSAID therapy. If a serious GI adverse event is suspected, promptly initiate evaluation and treatment, and discontinue diclofenac sodium topical solution until a serious GI adverse event is ruled out.

In the setting of concomitant use of low-dose aspirin for cardiac prophylaxis, monitor patients more closely for evidence of GI bleeding .

5.3Hepatotoxicity In

clinical trials of oral diclofenac containing products, meaningful elevations (i.e., more than 3 times the ULN) of AST (SGOT) occurred in about 2% of approximately 5,700 patients at some time during diclofenac treatment (ALT was not measured in all studies). In a large, open-label, controlled trial of 3,700 patients treated with oral diclofenac for 2 to 6 months, patients were monitored first at 8 weeks and 1,200 patients were monitored again at 24 weeks. Meaningful elevations of ALT and/or AST occurred in about 4% of 3,700 patients and included marked elevations (greater than 8 times the ULN) in about 1% of the 3,700 patients.

In that open-label study, a higher incidence of borderline (less than 3 times the ULN), moderate (3 to 8 times the ULN), and marked (greater than 8 times the ULN) elevations of ALT or AST was observed in patients receiving diclofenac when compared to other NSAIDs. Elevations in transaminases were seen more frequently in patients with osteoarthritis than in those with rheumatoid arthritis. Almost all meaningful elevations in transaminases were detected before patients became symptomatic.

Abnormal tests occurred during the first 2 months of therapy with oral diclofenac in 42 of the 51 patients in all trials who developed marked transaminase elevations. In postmarketing reports, cases of drug-induced hepatotoxicity have been reported in the first month, and in some cases, the first 2 months of NSAID therapy, but can occur at any time during treatment with diclofenac. Postmarketing surveillance has reported cases of severe hepatic reactions, including liver necrosis, jaundice, fulminant hepatitis with and without jaundice, and liver failure.

Some of these reported cases resulted in fatalities or liver transplantation. In a European retrospective population-based, case-controlled study, 10 cases of oral diclofenac associated drug-induced liver injury with current use compared with non-use of diclofenac were associated with a statistically significant 4-fold adjusted odds ratio of liver injury. In this particular study, based on an overall number of 10 cases of liver injury associated with diclofenac, the adjusted odds ratio increased further with female gender, doses of 150 mg or more, and duration of use for more than 90 days.

Physicians should measure transaminases at baseline and periodically in patients receiving long-term therapy with diclofenac, because severe hepatotoxicity may develop without a prodrome of distinguishing symptoms. The optimum times for making the first and subsequent transaminase measurements are not known. Based on clinical trial data and postmarketing experiences, transaminases should be monitored within 4 to 8 weeks after initiating treatment with diclofenac.

However, severe hepatic reactions can occur at any time during treatment with diclofenac. If abnormal liver tests persist or worsen, if clinical signs and/or symptoms consistent with liver disease develop, or if systemic manifestations occur (e.g., eosinophilia, rash, abdominal pain, diarrhea, dark urine, etc.), diclofenac sodium topical solution should be discontinued immediately. Inform patients of the warning signs and symptoms of hepatotoxicity (e.g., nausea, fatigue, lethargy, diarrhea, pruritus, jaundice, right upper quadrant tenderness, and "flu-like" symptoms).

If clinical signs and symptoms consistent with liver disease develop, or if systemic manifestations occur (e.g., eosinophilia, rash, etc.), discontinue diclofenac sodium topical solution immediately, and perform a clinical evaluation of the patient. To minimize the potential risk for an adverse liver-related event in patients treated with diclofenac sodium topical solution, use the lowest effective dose for the shortest duration possible. Exercise caution when prescribing diclofenac sodium topical solution with concomitant drugs that are known to be potentially hepatotoxic (e.g., acetaminophen, antibiotics, antiepileptics).

5.4Hypertension NSAIDs,

including diclofenac, can lead to new onset of hypertension or worsening of preexisting hypertension, either of which may contribute to the increased incidence of CV events. Patients taking angiotensin converting enzyme (ACE) inhibitors, thiazide diuretics, or loop diuretics may have impaired response to these therapies when taking NSAIDs . Monitor blood pressure (BP) during the initiation of NSAID treatment and throughout the course of therapy.

5.5Heart 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 in some patients treated with NSAIDs.

Use of diclofenac may blunt the CV effects of several therapeutic agents used to treat these medical conditions (e.g., diuretics, ACE inhibitors, or angiotensin receptor blockers [ARBs]) . Avoid the use of diclofenac sodium topical solution in patients with severe heart failure unless the benefits are expected to outweigh the risk of worsening heart failure. If diclofenac sodium topical solution is used in patients with severe heart failure, monitor patients for signs of worsening heart failure.

5.6Renal Toxicity and Hyperkalemia Renal Toxicity

Long-term administration of NSAIDs has resulted in renal papillary necrosis and other renal injury. Renal toxicity has also been seen in patients in whom renal prostaglandins have a compensatory role in the maintenance of renal perfusion. In these patients, administration of an NSAID may cause a dose-dependent reduction in prostaglandin formation and, secondarily, in renal blood flow, which may precipitate overt renal decompensation.

Patients at greatest risk of this reaction are those with impaired renal function, dehydration, hypovolemia, heart failure, liver dysfunction, those taking diuretics and ACE-inhibitors or ARBs, and the elderly. Discontinuation of NSAID therapy is usually followed by recovery to the pretreatment state. No information is available from controlled clinical studies regarding the use of diclofenac sodium topical solution in patients with advanced renal disease.

The renal effects of diclofenac sodium topical solution may hasten the progression of renal dysfunction in patients with preexisting renal disease. Correct volume status in dehydrated or hypovolemic patients prior to initiating diclofenac sodium topical solution. Monitor renal function in patients with renal or hepatic impairment, heart failure, dehydration, or hypovolemia during use of diclofenac sodium topical solution . Avoid the use of diclofenac sodium topical solution in patients with advanced renal disease unless the benefits are expected to outweigh the risk of worsening renal function.

If diclofenac sodium topical solution is used in patients with advanced renal disease, monitor patients for signs of worsening renal function. Hyperkalemia Increases in serum potassium concentration, including hyperkalemia, have been reported with use of NSAIDs, even in some patients without renal impairment. In patients with normal renal function, these effects have been attributed to a hyporeninemic-hypoaldosteronism state.

5.7Anaphylactic Reactions Diclofenac

has been associated with anaphylactic reactions in patients with and without known hypersensitivity to diclofenac and in patients with aspirin-sensitive asthma . Seek emergency help if an anaphylactic reaction occurs.

5.8Exacerbation of Asthma Related to Aspirin Sensitivity

A subpopulation of patients with asthma may have aspirin-sensitive asthma which may include chronic rhinosinusitis complicated by nasal polyps; severe, potentially fatal bronchospasm; and/or intolerance to aspirin and other NSAIDs. Because cross-reactivity between aspirin and other NSAIDs has been reported in such aspirin-sensitive patients, diclofenac sodium topical solution is contraindicated in patients with this form of aspirin sensitivity . When diclofenac sodium topical solution is used in patients with preexisting asthma (without known aspirin sensitivity), monitor patients for changes in the signs and symptoms of asthma.

5.9Serious Skin Reactions NSAIDs,

including diclofenac, can cause serious skin adverse reactions such as exfoliative dermatitis, Stevens-Johnson Syndrome (SJS), and toxic epidermal necrolysis (TEN), which can be fatal. NSAIDs can also cause fixed drug eruption (FDE). FDE may present as a more severe variant known as generalized bullous fixed drug eruption (GBFDE), which can be life-threatening.

These serious events may occur without warning. Inform patients about the signs and symptoms of serious skin reactions, and to discontinue the use of diclofenac sodium topical solution at the first appearance of skin rash or any other sign of hypersensitivity. Diclofenac sodium topical solution is contraindicated in patients with previous serious skin reactions to NSAIDs . Do not apply diclofenac sodium topical solution to open skin wounds, infections, inflammations, or exfoliative dermatitis, as it may affect absorption and tolerability of the drug.

5.10Drug Reaction with Eosinophilia and Systemic Symptoms

(DRESS) Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) has been reported in patients taking NSAIDs such as diclofenac sodium topical solution. Some of these events have been fatal or life-threatening. DRESS typically, although not exclusively, presents with fever, rash, lymphadenopathy, and/or facial swelling.

Other clinical manifestations may include hepatitis, nephritis, hematological abnormalities, myocarditis, or myositis. Sometimes symptoms of DRESS may resemble an acute viral infection. Eosinophilia is often present. Because this disorder is variable in its presentation, other organ systems not noted here may be involved.

It is important to note that early manifestations of hypersensitivity, such as fever or lymphadenopathy, may be present even though rash is not evident. If such signs or symptoms are present, discontinue diclofenac sodium topical solution and evaluate the patient immediately.

5.11Fetal Toxicity Premature Closure of Fetal

Ductus Arteriosus Avoid use of NSAIDs, including diclofenac sodium topical solution, in pregnant women at about 30 weeks gestation and later. NSAIDs, including diclofenac sodium topical solution, increase the risk of premature closure of the fetal ductus arteriosus at approximately this gestational age. Oligohydramnios/Neonatal Renal Impairment Use of NSAIDs, including diclofenac sodium topical solution, at about 20 weeks gestation or later in pregnancy may cause fetal renal dysfunction leading to oligohydramnios and, in some cases, neonatal renal impairment.

These adverse outcomes are seen, on average, after days to weeks of treatment, although oligohydramnios has been infrequently reported as soon as 48 hours after NSAID initiation. Oligohydramnios is often, but not always, reversible with treatment discontinuation. Complications of prolonged oligohydramnios may, for example, include limb contractures and delayed lung maturation.

In some postmarketing cases of impaired neonatal renal function, invasive procedures such as exchange transfusion or dialysis were required. If NSAID treatment is necessary between about 20 and 30 weeks gestation, limit diclofenac sodium topical solution use to the lowest effective dose and shortest duration possible. Consider ultrasound monitoring of amniotic fluid if diclofenac sodium topical solution treatment extends beyond 48 hours.

Discontinue diclofenac sodium topical solution if oligohydramnios occurs and follow up according to clinical practice .

5.12Hematologic Toxicity Anemia

has occurred in NSAID-treated patients. This may be due to occult or gross blood loss, fluid retention, or an incompletely described effect on erythropoiesis. If a patient treated with diclofenac sodium topical solution has any signs or symptoms of anemia, monitor hemoglobin or hematocrit.

NSAIDs, including diclofenac sodium topical solution, may increase the risk of bleeding events. Co-morbid conditions such as coagulation disorders or concomitant use of warfarin, other anticoagulants, antiplatelet agents (e.g., aspirin), serotonin reuptake inhibitors (SSRIs) and serotonin norepinephrine reuptake inhibitors (SNRIs) may increase this risk. Monitor these patients for signs of bleeding .

5.13Masking of Inflammation and Fever The

pharmacological activity of diclofenac sodium topical solution in reducing inflammation, and possibly fever, may diminish the utility of diagnostic signs in detecting infections.

5.14Laboratory Monitoring Because

serious GI bleeding, hepatotoxicity, and renal injury can occur without warning symptoms or signs, consider monitoring patients on long-term NSAID treatment with a CBC and a chemistry profile periodically

5.15Sun Exposure Instruct

patients to avoid exposure to natural or artificial sunlight on treated knee(s) because studies in animals indicated topical diclofenac treatment resulted in an earlier onset of ultraviolet light-induced skin tumors. The potential effects of diclofenac sodium topical solution on skin response to ultraviolet damage in humans are not known.

5.16Eye Exposure Avoid

contact of diclofenac sodium topical solution with eyes and mucosa. Advise patients that if eye contact occurs, immediately wash out the eye with water or saline and consult a physician if irritation persists for more than an hour.

5.17Oral Nonsteroidal Anti-Inflammatory Drugs Concomitant

use of oral NSAIDs with diclofenac sodium topical solution, 1.5% resulted in a higher rate of rectal hemorrhage, more frequent abnormal creatinine, urea and hemoglobin. Therefore, do not use combination therapy with diclofenac sodium topical solution and an oral NSAID unless the benefit outweighs the risk and conduct periodic laboratory evaluations.

Known hypersensitivity to diclofenac or any components of the drug product. History of asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDs. In the setting of coronary artery bypass graft (CABG) surgery. Diclofenac sodium topical solution is contraindicated in the following patients: Known hypersensitivity (e.g., anaphylactic reactions and serious skin reactions) to diclofenac or any components of the drug product History of asthma, urticaria, or other allergic-type reactions after taking aspirin or other NSAIDs.

Severe, sometimes fatal, anaphylactic reactions to NSAIDs have been reported in such patients In the setting of coronary artery bypass graft (CABG) surgery

5.11Fetal Toxicity Premature Closure of Fetal

Ductus Arteriosus Avoid use of NSAIDs, including diclofenac sodium topical solution, in pregnant women at about 30 weeks gestation and later. NSAIDs, including diclofenac sodium topical solution, increase the risk of premature closure of the fetal ductus arteriosus at approximately this gestational age. Oligohydramnios/Neonatal Renal Impairment Use of NSAIDs, including diclofenac sodium topical solution, at about 20 weeks gestation or later in pregnancy may cause fetal renal dysfunction leading to oligohydramnios and, in some cases, neonatal renal impairment.

These adverse outcomes are seen, on average, after days to weeks of treatment, although oligohydramnios has been infrequently reported as soon as 48 hours after NSAID initiation. Oligohydramnios is often, but not always, reversible with treatment discontinuation. Complications of prolonged oligohydramnios may, for example, include limb contractures and delayed lung maturation.

In some postmarketing cases of impaired neonatal renal function, invasive procedures such as exchange transfusion or dialysis were required. If NSAID treatment is necessary between about 20 and 30 weeks gestation, limit diclofenac sodium topical solution use to the lowest effective dose and shortest duration possible. Consider ultrasound monitoring of amniotic fluid if diclofenac sodium topical solution treatment extends beyond 48 hours.

Discontinue diclofenac sodium topical solution if oligohydramnios occurs and follow up according to clinical practice .

8.1Pregnancy Risk Summary Use of NSAIDs,

including diclofenac sodium topical solution, can cause premature closure of the fetal ductus arteriosus and fetal renal dysfunction leading to oligohydramnios and, in some cases, neonatal renal impairment. Because of these risks, limit dose and duration of diclofenac sodium topical solution use between about 20 and 30 weeks of gestation, and avoid diclofenac sodium topical solution use at about 30 weeks of gestation and later in pregnancy . Premature Closure of Fetal Ductus Arteriosus Use of NSAIDs, including diclofenac sodium topical solution, at about 30 weeks gestation or later in pregnancy increases the risk of premature closure of the fetal ductus arteriosus. Oligohydramnios/Neonatal Renal Impairment Use of NSAIDs at about 20 weeks gestation or later in pregnancy has been associated with cases of fetal renal dysfunction leading to oligohydramnios, and in some cases, neonatal renal impairment.

Data from observational studies regarding other potential embryofetal risks of NSAID use in women in the first or second trimesters of pregnancy are inconclusive. In animal reproduction studies, no evidence of malformations were observed in mice, rats, or rabbits given diclofenac during the period of organogenesis at doses up to approximately 0.6, 0.6, and 1.3 times, respectively, the maximum recommended human dose (MRHD) of 162 mg diclofenac sodium via diclofenac sodium topical solution, despite the presence of maternal and fetal toxicity at these doses . Based on animal data, prostaglandins have been shown to have an important role in endometrial vascular permeability, blastocyst implantation, and decidualization. In animal studies, administration of prostaglandin synthesis inhibitors such as diclofenac, resulted in increased pre- and post-implantation loss.

Prostaglandins also have been shown to have an important role in fetal kidney development. In published animal studies, prostaglandin synthesis inhibitors have been reported to impair kidney development when administered at clinically relevant doses. The estimated background risk of major birth defects and miscarriage for the indicated population(s) is unknown.

All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Clinical Considerations Fetal/Neonatal Adverse Reactions Premature Closure of the Fetal Ductus Arteriosus: Avoid use of NSAIDs in women at about 30 weeks gestation and later in pregnancy, because NSAIDs, including diclofenac sodium topical solution, can cause premature closure of the fetal ductus arteriosus . Oligohydramnios/Neonatal Renal Impairment: If an NSAID is necessary at about 20 weeks gestation or later in pregnancy, limit the use to the lowest effective dose and shortest duration possible.

If diclofenac sodium topical solution treatment extends beyond 48 hours, consider monitoring with ultrasound for oligohydramnios. If oligohydramnios occurs, discontinue diclofenac sodium topical solution and follow up according to clinical practice . Labor or Delivery: There are no studies on the effects of diclofenac sodium topical solution during labor or delivery. In animal studies, NSAIDs, including diclofenac inhibit prostaglandin synthesis, cause delayed parturition, and increase the incidence of stillbirth.

Data Human Data Premature Closure of Fetal Ductus Arteriosus: Published literature reports that the use of NSAIDs at about 30 weeks of gestation and later in pregnancy may cause premature closure of the fetal ductus arteriosus. Oligohydramnios/Neonatal Renal Impairment: Published studies and postmarketing reports describe maternal NSAID use at about 20 weeks gestation or later in pregnancy associated with fetal renal dysfunction leading to oligohydramnios, and in some cases, neonatal renal impairment. These adverse outcomes are seen, on average, after days to weeks of treatment, although oligohydramnios has been infrequently reported as soon as 48 hours after NSAID initiation.

In many cases, but not all, the decrease in amniotic fluid was transient and reversible with cessation of the drug. There have been a limited number of case reports of maternal NSAID use and neonatal renal dysfunction without oligohydramnios, some of which were irreversible. Some cases of neonatal renal dysfunction required treatment with invasive procedures, such as exchange transfusion or dialysis.

Methodological limitations of these postmarketing studies and reports include lack of a control group; limited information regarding dose, duration, and timing of drug exposure; and concomitant use of other medications. These limitations preclude establishing a reliable estimate of the risk of adverse fetal and neonatal outcomes with maternal NSAID use. Because the published safety data on neonatal outcomes involved mostly preterm infants, the generalizability of certain reported risks to the full-term infant exposed to NSAIDs through maternal use is uncertain.

Animal data: Reproductive and developmental studies in animals demonstrated that diclofenac sodium administration during organogenesis did not produce malformations despite the induction of maternal toxicity and fetal toxicity in mice at oral doses up to 20 mg/kg/day (approximately 0.6 times the maximum recommended human dose [MRHD] of diclofenac sodium topical solution, 162 mg diclofenac sodium/day, based on body surface area (BSA) comparison), and in rats and rabbits at oral doses up to 10 mg/kg/day (approximately 0.6 and 1.3-times, respectively, the MRHD based on BSA comparison). Published reproductive and developmental studies of dimethyl sulfoxide (DMSO, the solvent used in diclofenac sodium topical solution) are equivocal as to potential teratogenicity. In a study in which pregnant rats were orally administered 2 or 4 mg/kg diclofenac (0.12 and 0.24 times the MRHD, respectively, based on BSA comparison) from Gestation Day 15 through Lactation Day 21, significant maternal toxicity (peritonitis, mortality) was noted.

These maternally toxic doses were associated with dystocia, prolonged gestation, reduced fetal weights and growth, and reduced fetal survival. Diclofenac has been shown to cross the placental barrier in mice and rats. In published studies, diclofenac administration to pregnant rats prolonged gestation and produced liver toxicity and neuronal loss in offspring (1 mg/kg, IP; 0.06 times the MRHD based on BSA comparison), impaired nephrogenesis in the kidney (3.6 mg/kg, IP; 0.2 times the MRHD based on BSA comparison), and caused adverse effects on the developing testes (6.1 mg/kg, oral; 0.4 times the MRHD based on BSA comparison).

8.3Females and Males of Reproductive Potential Infertility

Females: Based on the mechanism of action, the use of prostaglandin-mediated NSAIDs, including diclofenac sodium topical solution, may delay or prevent rupture of ovarian follicles, which has been associated with reversible infertility in some women. Published animal studies have shown that administration of prostaglandin synthesis inhibitors has the potential to disrupt prostaglandin-mediated follicular rupture required for ovulation. Small studies in women treated with NSAIDs have also shown a reversible delay in ovulation.

Consider withdrawal of NSAIDs, including diclofenac sodium topical solution, in women who have difficulties conceiving or who are undergoing investigation of infertility. Males: Published studies in adult male rodents report that diclofenac, at clinically relevant doses, can produce adverse effects on male reproductive tissues. The impact of these findings on male fertility is not clear .

The following adverse reactions are discussed in greater detail in other sections of the labeling: Cardiovascular Thrombotic Events GI Bleeding, Ulceration and Perforation Hepatotoxicity Hypertension Heart Failure and Edema Renal Toxicity and Hyperkalemia Anaphylactic Reactions Serious Skin Reactions Hematologic Toxicity The most common adverse reactions with diclofenac sodium topical solution are application site reactions. To report SUSPECTED ADVERSE REACTIONS, contact Lupin Pharmaceuticals, Inc. at 1-800-399-2561 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch .

6.1Clinical 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. Diclofenac Sodium Topical Solution The data described below reflect exposure to diclofenac sodium topical solution of 130 patients treated for 4 weeks (mean duration of 28 days) in one Phase 2 controlled trial. This population's mean age was approximately 60 years, 85% of patients were Caucasian, 65% were females, and all patients had primary osteoarthritis.

The most common adverse events with diclofenac sodium topical solution were application site skin reactions. These events were the most common reason for withdrawing from the study. Application Site Reactions: In this controlled trial, application site reactions were characterized by one or more of the following: dryness (22%), exfoliation (7%), erythema (4%), pruritus (2%), pain (2%), induration (2%), rash (2%), and scabbing (<1%).

Other Common Adverse Reactions: Table 1 lists all adverse reactions occurring in >1% of patients receiving diclofenac sodium topical solution, where the rate in the diclofenac sodium topical solution group exceeded vehicle, from a controlled study conducted in patients with osteoarthritis. Table 1: Incidence of Adverse Reactions Occurring in >1% of Subjects with Osteoarthritis Using Diclofenac Sodium Topical Solution and More Often than in Subjects with OA Using Vehicle Control (Pooled) Adverse Reaction Diclofenac Sodium Topical Solution N = 130 n (%) Vehicle Control N = 129 n (%) Urinary tract infection 4 (3%) 1 (<1%) Application site induration 2 (2%) 1 (<1%) Contusion 2 (2%) 1 (<1%) Sinus congestion 2 (2%) 1 (<1%) Nausea 2 (2%) 0 Diclofenac Sodium Topical Solution 1.5% The safety of diclofenac sodium topical solution, 2% is based in part, on prior experience with diclofenac sodium topical solution, 1.5%. The data described below reflect exposure to diclofenac sodium topical solution, 1.5% of 911 patients treated between 4 and 12 weeks (mean duration of 49 days) in seven Phase 3 controlled trials, as well as exposure of 793 patients treated in an open-label study, including 463 patients treated for at least 6 months, and 144 patients treated for at least 12 months. The population mean age was approximately 60 years, 89% of patients were Caucasian, 64% were females, and all patients had primary osteoarthritis.

The most common adverse events with diclofenac sodium topical solution, 1.5% were application site skin reactions. These events were the most common reason for withdrawing from the studies. Application Site Reactions: In controlled trials, application site reactions were characterized by one or more of the following: dryness, erythema, induration, vesicles, paresthesia, pruritus, vasodilation, acne, and urticaria.

The most frequent of these reactions were dry skin (32%), contact dermatitis characterized by skin erythema and induration (9%), contact dermatitis with vesicles (2%) and pruritus (4%). In one controlled trial, a higher rate of contact dermatitis with vesicles (4%) was observed after treatment of 152 subjects with the combination of diclofenac sodium topical solution, 1.5% and oral diclofenac. In the open-label uncontrolled long-term safety study, contact dermatitis occurred in 13% and contact dermatitis with vesicles in 10% of patients, generally within the first 6 months of exposure, leading to a withdrawal rate for an application site event of 14%. Other Common Adverse Reactions: In controlled trials, subjects treated with diclofenac sodium topical solution, 1.5% experienced some adverse events associated with the NSAID class more frequently than subjects using placebo (constipation, diarrhea, dyspepsia, nausea, flatulence, abdominal pain, edema; see Table 2).

The combination of diclofenac sodium topical solution, 1.5% and oral diclofenac, compared to oral diclofenac alone, resulted in a higher rate of rectal hemorrhage (3% vs. less than 1%), and more frequent abnormal creatinine (12% vs. 7%), urea (20% vs. 12%), and hemoglobin (13% vs. 9%), but no difference in elevation of liver transaminases. Table 2 lists all adverse reactions occurring in ≥1% of patients receiving diclofenac sodium topical solution, 1.5%, where the rate in the diclofenac sodium topical solution, 1.5% group exceeded placebo, from seven controlled studies conducted in patients with osteoarthritis. Since these trials were of different durations, these percentages do not capture cumulative rates of occurrence.

Table 2: Adverse Reactions Occurring in ≥1% of Patients Treated with Diclofenac Sodium Topical Solution, 1.5% Topical Solution in Placebo and Oral Diclofenac-Controlled Trials Treatment Group: Diclofenac Sodium Topical Solution, 1.5% N=911 Topical Placebo N=332 Adverse Reaction N (%) N (%) Dry Skin (Application Site) 292 17 Contact Dermatitis (Application Site) 83 6 Dyspepsia 72 13 Abdominal Pain 54 10 Flatulence 35 1 (<1) Pruritus (Application Site) 34 7 Diarrhea 33 7 Nausea 33 3 Pharyngitis 40 13 Constipation 29 1 (<1) Edema 26 0 Rash (Non-Application Site) 25 5 Infection 25 8 Ecchymosis 19 1 (<1) Dry Skin (Non-Application Site) 19 1 (<1) Contact Dermatitis, vesicles (Application Site) 18 0 Paresthesia (Non-Application Site) 14 3 (<1) Accidental Injury 22 7 Pruritus (Non-Application Site) 15 2 (<1) Sinusitis 10 2 (<1) Halitosis 11 1 (<1) Application Site Reaction (not otherwise specified) 11 3 (<1)

6.2Postmarketing Experience In

postmarketing surveillance, the following adverse reactions have been reported during post-approval use of diclofenac sodium topical solution, 1.5%. 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. Body as a Whole: abdominal pain, accidental injury, allergic reactions, asthenia, back pain, body odor, chest pain, edema, face edema, halitosis, headache, neck rigidity, pain Cardiovascular: palpitation, cardiovascular disorder Gastrointestinal: diarrhea, dry mouth, dyspepsia, gastroenteritis, decreased appetite, lip swelling, mouth ulceration, nausea, rectal hemorrhage, ulcerative stomatitis, swollen tongue Metabolic and Nutritional: creatinine increased Musculoskeletal: leg cramps, myalgia Nervous: depression, dizziness, drowsiness, lethargy, paresthesia at application site Respiratory: asthma, dyspnea, laryngismus, laryngitis, pharyngitis, throat swelling Skin and Appendages: At the Application Site: rash, skin burning sensation; Other Skin and Appendages Adverse Reactions: eczema, skin discoloration, urticaria, exfoliative dermatitis, Stevens-Johnson Syndrome (SJS), toxic epidermal necrolysis (TEN), and fixed drug eruption (FDE). Special Senses: abnormal vision, blurred vision, cataract, ear pain, eye disorder, eye pain, taste perversion Vascular: blood pressure increased, hypertension