Orthrexo
Diclofenac Sodium and Menthol, Methyl salicylate · Kit
Uses
Diclofenac sodium topical solution is indicated for the treatment of signs and symptoms of osteoarthritis of the knee(s). Diclofenac sodium topical solution is a nonsteroidal anti-inflammatory drug indicated for the treatment of signs and symptoms of osteoarthritis of the knee(s). ( 1 ) For the temporary relief of minor aches and pains of muscles and joints associated with simple backache, arthritis, strains, bruises, and sprains.
Dosage and administration
Use the lowest effective dosage for the shortest duration consistent with individual patient treatment goals. The recommended dose is 40 drops on each painful knee, 4 times a day. ( 2 ) Apply diclofenac sodium topical solution to clean, dry skin. ( 2.1 ) Dispense diclofenac sodium topical solution 10 drops at a time either directly onto the knee or first into the hand and then onto the knee. Spread diclofenac sodium topical solution evenly around front, back and sides of the knee. Repeat this procedure until 40 drops have been applied and the knee is completely covered with solution. ( 2.1 ) 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). ( 2.2 ) Do not get diclofenac sodium topical solution in your eyes, nose or mouth. ( 2.2 ) 2.1 General Dosing Instructions Use the lowest effective dosage for the shortest duration consistent with individual patient treatment goals [see Warning and Precautions (5.2) ] For the relief of the signs and symptoms of osteoarthritis of the knee(s), the recommended dose is 40 drops per knee, 4 times a day. Apply diclofenac sodium topical solution to clean, dry skin. To avoid spillage, dispense diclofenac sodium topical solution 10 drops at a time either directly onto the knee or first into the hand and then onto the knee. Spread diclofenac sodium topical solution evenly around front, back and sides of the knee. Repeat this procedure until 40 drops have been applied and the knee is completely covered with solution. To treat the other knee, if symptomatic, repeat the procedure. 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. 2.2 Special 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 or 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. Adults and children 12 years of age and older: apply to affected area not more than 3 to 4 times daily wash hands with soap and water after apply Children under 12 years of age: ask a doctor
Dosage forms and strengths
Diclofenac sodium topical solution: 1.5% w/w Diclofenac sodium topical solution 1.5% w/w ( 3 )
Contraindications
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 [see Warnings and Precautions (5.7, 5.9) ] . 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 [see Warnings and Precautions (5.7, 5.8) ] . In the setting of coronary artery bypass graft (CABG) surgery [see Warnings and Precautions (5.1) ] . Known hypersensitivity to diclofenac or any components of the drug product. ( 4 ) History of asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDs. ( 4 ) In the setting of CABG surgery. ( 4 )
Warnings and precautions
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. ( 5.3 ) 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. ( 5.5 ) 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. ( 5.6 ) Anaphylactic Reactions: Seek emergency help if an anaphylactic reaction occurs. ( 5.7 ) 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). ( 5.8 ) Serious Skin Reactions: Discontinue diclofenac sodium topical solution at first appearance of skin rash or other signs of hypersensitivity. ( 5.9 ) Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) : Discontinue and evaluate clinically. ( 5.10 ). 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. ( 5.15 ) Eye Contact: Avoid contact of diclofenac sodium topical solution with eyes and mucosa. ( 5.16 ) Oral Nonsteroidal Anti-inflammatory Drugs: Avoid concurrent use with oral NSAIDs. ( 5.17 ) 5.1 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 diclofenac, increases the risk of serious gastrointestinal (GI) events [see Warnings and Precautions (5.2) ] . 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 [see Contraindications (4) ] . 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. 5.2 Gastrointestinal 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.
Warnings
For external use only Do not use: On wounds or damaged skin With a heating pad On a child under 12 years of age with arthritis-like conditions Ask a doctor before use if you haveredness over the affected area When using this product Avoid contact with eyes Do not bandage tightly Stop use and ask a doctor if Condition worsens or symptoms persist for more than 7 days Symptoms clear up and occur again within a few days Excessive skin irritation occurs
Side effects
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 with diclofenac sodium topical solution are application site reactions. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Amneal Pharmaceuticals at 1-877-835-5472 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. The data described below reflect exposure to diclofenac sodium topical solution 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 Caucasians, 64% 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 studies. Application Site Reactions In controlled trials, the most common treatment-related adverse events in patients receiving diclofenac sodium topical solution were application site skin reactions. 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 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%. Adverse Events Common to the NSAID Class In controlled trials, subjects treated with diclofenac sodium topical solution 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 1 ). The combination of diclofenac sodium topical solution 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 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 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 1: Adverse Reactions occurring in ≥ 1% of patients treated with diclofenac sodium topical solution in placebo and oral diclofenac-controlled trials. Treatment Group: Diclofenac sodium topical solution N=911 Topical Placebo N=332 Adverse Reaction † N (%) N (%) Dry Skin (Application Site) 292 (32) 17 (5) Contact Dermatitis (Application Site) 83 (9) 6 (2) Dyspepsia 72 (8) 13 (4) Abdominal Pain 54 (6) 10 (3) Flatulence 35 (4) 1 (<1) Pruritus (Application Site) 34 (4) 7 (2) Diarrhea 33 (4) 7 (2) Nausea 33 (4) 3 (1) Pharyngitis 40 (4) 13 (4) Constipation 29 (3) 1 (<1) Edema 26 (3) 0 Rash (Non-Application Site) 25 (3) 5 (2) Infection 25 (3) 8 (2) Ecchymosis 19 (2) 1 (<1) Dry Skin (Non-Application Site) 19 (2) 1 (<1) Contact Dermatitis, vesicles (Application Site) 18 (2) 0 Paresthesia (Non-Application Site) 14 (2) 3 (<1) Accidental Injury 22 (2) 7 (2) Pruritus (Non-Application Site) 15 (2) 2 (<1) Sinusitis 10 (1) 2 (<1) Halitosis 11 (1) 1 (<1) Application Site Reaction (not otherwise specified) 11 (1) 3 (<1) † Preferred Term according to COSTART 6.2 Postmarketing Experience In non-U.S. postmarketing surveillance, the following adverse reactions have been reported during post-approval use of diclofenac sodium topical solution. 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.
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 sodium topical solution 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: 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 NSAID alone [see Warnings and Precautions (5.2) ] Intervention: Concomitant use of diclofenac sodium topical solution and analgesic doses of aspirin is not generally recommended because of the increased risk of bleeding [see Warnings and Precautions (5.12) ] . Diclofenac sodium topical solution 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 sodium topical solution and ACE-inhibitors, ARBs, or beta-blockers, monitor blood pressure to ensure that the desired blood pressure is obtained. During concomitant use of diclofenac sodium topical solution 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 diclofenac sodium topical solution 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 diclofenac with digoxin has been reported to increase the serum concentration and prolong the half-life digoxin. Intervention: During concomitant use of diclofenac sodium topical solution 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 sodium topical solution and lithium, monitor patients for signs of lithium toxicity. Methotrexate Clinical Impact: Concomitant use of NSAIDs and methotrexate may increase the risk of methotrexate toxicity (e.g., neutropenia, thrombocytopenia, renal dysfunction). Intervention: During concomitant use of diclofenac sodium topical solution and methotrexate, monitor patients for methotrexate toxicity. Cyclosporine Clinical Impact: Concomitant use of diclofenac sodium topical solution and cyclosporine may increase cyclosporine’s nephrotoxicity. Intervention: During concomitant use of diclofenac sodium topical solution and cyclosporine, monitor patients for signs or 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 and Precautions (5.2) ] . Concomitant use of oral NSAIDs with diclofenac sodium topical solution has been evaluated in one Phase 3 controlled trial and in combination with 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%). Intervention: The concomitant use of diclofenac with other NSAIDs or salicyclates is not recommended. 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 Pemetrexed Clinical Impact: Concomitant use of diclofenac sodium topical solution and pemetrexed may increase the risk of pemetrexed-associated myelosuppression, renal, and GI toxicity (see the pemetrexed prescribing information).
Use in specific populations
Use of NSAIDs during the third trimester of pregnancy increases the risk of premature closure of the fetal ductus arteriosus. Avoid use of NSAIDs in pregnant women starting at 30 weeks gestation. ( 5.11 , 8.1 ) Infertility: NSAIDs are associated with reversible infertility. Consider withdrawal of diclofenac sodium topical solution in women who have difficulties conceiving. ( 8.3 ) 8.1 Pregnancy 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 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 ( see Clinical Considerations, Data ). 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 potential embryo-fetal risks of NSAID use in women in the first or second trimesters of pregnancy are inconclusive. In animal reproduction studies, no evidence of teratogenicity was observed in mice, rats, or rabbits given diclofenac daily 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 diclofenac sodium topical solution, despite the presence of maternal and fetal toxicity at these doses (see Data). 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 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 (see Data). 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 (see Data) . 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.
Pregnancy
8.1 Pregnancy 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 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 ( see Clinical Considerations, Data ). 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 potential embryo-fetal risks of NSAID use in women in the first or second trimesters of pregnancy are inconclusive. In animal reproduction studies, no evidence of teratogenicity was observed in mice, rats, or rabbits given diclofenac daily 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 diclofenac sodium topical solution, despite the presence of maternal and fetal toxicity at these doses (see Data). 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 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 (see Data). 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 (see Data) . 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 teratogenicity 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, 154 mg/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.
Pediatric use
8.4 Pediatric Use Safety and effectiveness in pediatric patients have not been established.
Geriatric use
8.5 Geriatric Use Elderly patients, compared to younger patients, are a greater risk for NSAID-associated serious cardiovascular, gastrointestinal, and/or renal adverse reactions. If the anticipated benefit for the elderly patient outweighs these potential risks, start dosing at the low end of the dosing range, and monitor patients for adverse effects [see Warnings and Precautions (5.1 , 5.2 , 5.3 , 5.6 , 5.14 )] . Of the 911 patients treated with diclofenac sodium topical solution in seven controlled, Phase 3 clinical trials, 444 subjects were 65 years of age and over. There was no age-related difference in the incidence of adverse events. Of the 793 patients treated with diclofenac sodium topical solution in one open-labeled safety trial, 334 subjects were 65 years of age and over including 107 subjects 75 and over. There was no difference in the incidence of adverse events with long-term exposure to diclofenac sodium topical solution for this elderly population.
Overdosage
Symptoms following acute NSAID overdosages have been typically limited to lethargy, drowsiness, nausea, vomiting, and epigastric pain, which have been generally reversible with supportive care. Gastrointestinal bleeding has occurred. Hypertension, acute renal failure, respiratory depression, and coma have occurred, but were rare [see Warnings and Precautions (5.1, 5.2, 5.4, 5.6) ] . Manage patients with symptomatic and supportive care following an NSAID overdosage. There are no specific antidotes. Emesis is not recommended due to a possibility of aspiration and subsequent respiratory irritation by DMSO contained in diclofenac sodium topical solution. Consider activated charcoal (60 to 100 grams in adults, 1 to 2 grams per kg of body weight in pediatric patients) and/or osmotic cathartic in symptomatic patients seen within four hours of ingestion or in patients with a large overdosage (5 to 10 times the recommended dosage). Forced diuresis, alkalinization of urine, hemodialysis, or hemoperfusion may not be useful due to high protein binding. For additional information about overdose treatment, contact a poison control center (1-800-222-1222).
Description
Diclofenac sodium topical solution 1.5% is a nonsteroidal anti-inflammatory drug, available as a clear, colorless to faintly pink-orange solution for topical application. Diclofenac sodium topical solution contains 1.5% w/w diclofenac sodium, USP, a benzeneacetic acid derivative that is a nonsteroidal anti-inflammatory drug (NSAID), designated chemically as 2-[(2,6-dichlorophenyl)amino]-benzeneacetic acid, monosodium salt. It is a white to off-white crystalline powder, hygroscopic, and odorless that is freely soluble in methanol, soluble in alcohol, and sparingly soluble in water. The molecular weight is 318.13. Its molecular formula is C 14 H 10 Cl 2 NNaO 2 and it has the following structural formula. Each 1 mL of solution contains 16.05 mg of diclofenac sodium, USP. The inactive ingredients in diclofenac sodium topical solution include: alcohol, dimethyl sulfoxide USP (DMSO, 45.5% w/w), glycerin, propylene glycol, and purified water. Structural Formula
Mechanism of action
12.1 Mechanism of Action Diclofenac has analgesic, anti-inflammatory, and antipyretic properties. The mechanism of action of diclofenac sodium topical solution, like that of other NSAIDs, is not completely understood but involves inhibition of cyclooxygenase (COX-1 and COX-2). Diclofenac is a potent inhibitor of prostaglandin synthesis in vitro . Diclofenac 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 diclofenac is an inhibitor of prostaglandin synthesis, its mode of action may be due to a decrease of prostaglandins in peripheral tissues.
How supplied
Diclofenac sodium topical solution 1.5% w/w is supplied as a clear, colorless to faintly pink-orange solution containing 16.05 mg of diclofenac sodium per 1 mL of solution, in a white high density polyethylene bottle with a white low-density dropper cap. It is available as follows: 150 mL bottle NDC 65162-911-74 Storage Store at 20° to 25°C (68° to 77°F); excursions permitted between 15° to 30°C (59° to 86°F) [see USP Controlled Room Temperature].
Patient information
Advise the patient to read the FDA-approved patient labeling (Medication Guide) and Instructions for Use that accompanies each prescription dispensed. Inform patients, families, or their caregivers of the following information before initiating therapy with diclofenac sodium topical solution and periodically during the course of ongoing therapy. Cardiovascular Thrombotic Events Advise patients to be alert for the symptoms of cardiovascular thrombotic events, including chest pain, shortness of breath, weakness, or slurring of speech, and to report any of these symptoms to their health care provider immediately [see Warnings and Precautions (5.1) ] . Gastrointestinal Bleeding, Ulceration, and Perforation Advise patients to report symptoms of ulcerations and bleeding, including epigastric pain, dyspepsia, melena, and hematemesis to their health care provider. In the setting of concomitant use of low-dose aspirin for cardiac prophylaxis, inform patients of the increased risk for and the signs and symptoms of GI bleeding [see Warnings and Precautions (5.2) ] . Hepatotoxicity Inform patients of the warning signs and symptoms of hepatotoxicity (e.g., nausea, fatigue, lethargy, pruritus, diarrhea, jaundice, right upper quadrant tenderness, and “flu-like” symptoms). If these occur, instruct patients to stop diclofenac sodium topical solution and seek immediate medical therapy [see Warnings and Precautions (5.3) ] . Heart Failure and Edema Advise patients to be alert for the symptoms of congestive heart failure including shortness of breath, unexplained weight gain, or edema and to contact their healthcare provider if such symptoms occur [see Warnings and Precautions (5.5) ] . Anaphylactic Reactions Inform patients of the signs of an anaphylactic reaction (e.g., difficulty breathing, swelling of the face or throat). Instruct patients to seek immediate emergency help if these occur [see Contraindications (4) and Warnings and Precautions (5.7) ] . Serious Skin Reactions, including DRESS Advise patients to stop taking diclofenac sodium topical solution immediately if they develop any type of rash or fever and to contact their healthcare provider as soon as possible [see Warnings and Precautions (5.9 , 5.10 )] . Female Fertility Advise females of reproductive potential who desire pregnancy that NSAIDs, including diclofenac sodium topical solution, may be associated with a reversible delay in ovulation [see Use in Specific Populations (8.3) ] Fetal Toxicity Inform pregnant women to avoid use of diclofenac sodium topical solution and other NSAIDs starting at 30 weeks gestation because of the risk of the premature closing of the fetal ductus arteriosus. If treatment with diclofenac sodium topical solution is needed for a pregnant woman between about 20 to 30 weeks gestation, advise her that she may need to be monitored for oligohydramnios, if treatment continues for longer than 48 hours [see Warnings and Precautions (5.11) and Use in Specific Populations (8.1) ] . Avoid Concomitant Use of NSAIDs Inform patients that the concomitant use of diclofenac sodium topical solution with other NSAIDs or salicylates (e.g., diflunisal, salsalate) is not recommended due to the increased risk of gastrointestinal toxicity, and little or no increase in efficacy [see Warnings and Precautions (5.2) and Drug Interactions (7) ] . Alert patients that NSAIDs may be present in “over the counter” medications for treatment of colds, fever, or insomnia. Use of NSAIDS and Low-Dose Aspirin Inform patients not to use low-dose aspirin concomitantly with diclofenac sodium topical solution until they talk to their healthcare provider [see Drug Interactions (7) ] . Eye Exposure Instruct patients to avoid contact of diclofenac sodium topical solution with the 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. Prevention of Secondary Exposure Instruct patients to avoid skin-to-skin contact between other people and the knee(s) to which diclofenac sodium topical solution was applied until the knee(s) is completely dry. Application Site Reactions Diclofenac sodium topical solution can cause a localized skin reaction at the application site. Advise patients to contact their physicians as soon as possible if they develop any type of localized application site rash. Special Application Instructions Instruct patients not to apply diclofenac sodium topical solution to open skin wounds, infections, inflammations, or exfoliative dermatitis, as it may affect absorption and reduce tolerability of the drug. Instruct patients to wait until the area treated with diclofenac sodium topical solution is completely dry before applying sunscreen, insect repellant, lotion, moisturizer, cosmetics, or other topical medication. Instruct patients to minimize or avoid exposure of treated knee(s) to natural or artificial sunlight. Distributed by: Amneal Pharmaceuticals Bridgewater, NJ 08807 Rev. 05-2021-03
Label text from the FDA structured product label by V2 Pharma, LLC (revised Apr 2, 2026). Long sections are shortened; the complete label is on DailyMed.
Orthrexo NDC products (1)
| NDC | Strength & form | Labeler | Type |
|---|---|---|---|
| 72835-333 | Kit | V2 Pharma, LLC | UNAPPROVED DRUG OTHER |
Frequently asked questions
What is Orthrexo used for?
Diclofenac sodium topical solution is indicated for the treatment of signs and symptoms of osteoarthritis of the knee(s). Diclofenac sodium topical solution is a nonsteroidal anti-inflammatory drug indicated for the treatment of signs and symptoms of osteoarthritis of the knee(s). ( 1 ) For the temporary relief of minor aches and pains of muscles and joints associated with simple backache,…
What are the side effects of Orthrexo?
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… See the full label for the complete list.
Who makes Orthrexo?
Orthrexo is listed by 1 labeler in the FDA NDC directory, including V2 Pharma, LLC.