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Quick facts

How it is given
topical
Type
human prescription drug
RxNorm ID
1487074

We do not publish dosing. How much of this medicine to take, how often, and for how long depends on your age, weight, kidney and liver function, other conditions and other medicines. That is a decision for the person who prescribes or dispenses it. Follow the directions on your own pack and ask your pharmacist if anything is unclear.

What it is used to treat

Diclofenac sodium topical solution is indicated for the treatment of the pain of osteoarthritis of the knee(s). Diclofenac sodium topical solution is a nonsteroidal anti-inflammatory drug indicated for the treatment of the pain of osteoarthritis of the knee(s). ( 1 )

About this medicine

Diclofenac sodium topical solution USP, 2% w/w, contains diclofenac sodium, USP a benzeneacetic acid derivative that is a nonsteroidal anti-inflammatory drug, and is available as a clear, colorless to faintly pink or orange solution for topical application. The chemical name is 2 [(2,6-dichlorophenyl) amino]-benzeneacetic acid, monosodium salt. The molecular weight is 318.14. Its molecular formula is C 14 H 10 Cl 2 NNaO 2, and it has the following chemical structure. Each 1 gram of solution contains 20 mg of diclofenac sodium, USP. The inactive ingredients: dimethyl sulfoxide USP (DMSO, 45.5% w/w), ethanol (31.3% v/v), purified water, propylene glycol, and hydroxypropyl cellulose. structure

How it works

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.

Who should not take it

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 coronary artery bypass graft (CABG) surgery. ( 4 )

Warnings and cautions

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 , 5.15 ) 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. […]

Reported 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 )] The most common adverse reactions with diclofenac sodium topical solution are application site reactions. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Alembic Pharmaceuticals, Inc. at 1-866-210-9797or 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. 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%). […]

Interactions with other medicines

See Table 3 for clinically significant drug interactions with diclofenac. Table 3: 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 increased the 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 the 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). […]

Use in specific groups

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 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 (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 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 [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. […]

If too much is taken

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 overdosage treatment, contact a poison control center (1-800-222-1222).

Before you take anything new

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This page is built from the openFDA record of the U.S. Food and Drug Administration's approved labelling for this product, effective 17 January 2025. Label text has been shortened and reformatted for readability; safety wording has not been altered in meaning. FDA labelling describes products approved in the United States — brand names, strengths, formulations and approved uses may differ in your country. Always read the leaflet that comes with your own pack. PocketsInfo is not affiliated with, and is not endorsed by, the FDA. Retrieved 2026-07-30.