Diclofenac Potassium

FDA Drug Information • Also known as: Cambia, Diclofenac Potassium, Lofena, Zipsor

Brand Names: Cambia, Diclofenac Potassium, Lofena, Zipsor
Route: ORAL
Dosage Form: TABLET, COATED
Product Type: HUMAN PRESCRIPTION DRUG

⚠ Boxed Warning (Black Box)

WARNING: RISK OF SERIOUS CARDIOVASCULAR AND GASTROINTESTINAL EVENTS Cardiovascular Thrombotic Events

Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) cause an increased risk of serious cardiovascular thrombotic events, including myocardial infarction and stroke, which can be fatal. This risk may occur early in treatment and may increase with duration of use (see WARNINGS).

Diclofenac potassium tablets are contraindicated in the setting of coronary artery bypass graft (CABG) surgery (see CONTRAINDICATIONS, WARNINGS). Gastrointestinal Bleeding, Ulceration, and Perforation

NSAIDs cause an increased risk of serious gastrointestinal (GI) adverse events including bleeding, ulceration, and perforation of the stomach or intestines, which can be fatal. These events can occur at any time during use and without warning symptoms. Elderly patients and patients with a prior history of peptic ulcer disease and/or GI bleeding are at greater risk for serious GI events (see WARNINGS).

Description

DESCRIPTION Diclofenac potassium tablets, USP are a benzeneacetic acid derivative. Diclofenac potassium tablets are available for oral administration. Diclofenac potassium, USP is a white to off-white or slightly yellowish crystalline powder and is sparingly soluble in water at 25ºC. The chemical name is Potassium [ o -(2,6-dichloroanilino)phenyl] acetate. The molecular weight is 334.24. Its molecular formula is C 14 H 10 Cl 2 KNO 2, and it has the following structural formula: The inactive ingredients in diclofenac potassium tablets include: anhydrous lactose, colloidal silicon dioxide, croscarmellose sodium, glyceryl triacetate, hypromellose, magnesium stearate, microcrystalline cellulose, polydextrose, polyethylene glycol, sodium lauryl sulfate and titanium dioxide. Diclofenac Potassium Structural Formula

What Is Diclofenac Potassium Used For?

INDICATIONS AND USAGE Carefully consider the potential benefits and risks of diclofenac potassium tablets and other treatment options before deciding to use diclofenac potassium tablets. Use the lowest effective dose for the shortest duration consistent with individual patient treatment goals (see WARNINGS: Gastrointestinal Bleeding, Ulceration, and Perforation). Diclofenac potassium tablets are indicated:

For treatment of primary dysmenorrhea

For relief of mild to moderate pain

For relief of the signs and symptoms of osteoarthritis

For relief of the signs and symptoms of rheumatoid arthritis

Dosage and Administration

DOSAGE AND ADMINISTRATION Carefully consider the potential benefits and risks of diclofenac potassium tablets and other treatment options before deciding to use diclofenac potassium tablets. Use the lowest effective dose for the shortest duration consistent with individual patient treatment goals (see WARNINGS: Gastrointestinal Bleeding, Ulceration, and Perforation). After observing the response to initial therapy with diclofenac potassium tablets, the dose and frequency should be adjusted to suit an individual patient’s needs. For treatment of pain or primary dysmenorrhea the recommended dosage is 50 mg three times a day. With experience, physicians may find that in some patients an initial dose of 100 mg of diclofenac potassium tablets, followed by 50 mg doses, will provide better relief. For the relief of osteoarthritis the recommended dosage is 100-150 mg/day in divided doses, 50 mg twice a day or three times a day. For the relief of rheumatoid arthritis the recommended dosage is 150-200 mg/day in divided doses, 50 mg three times a day or four times a day. Different formulations of diclofenac (diclofenac sodium enteric-coated tablets; diclofenac sodium extended-release tablets; diclofenac potassium immediate-release tablets) are not necessarily bioequivalent even if the milligram strength is the same.

Side Effects (Adverse Reactions)

ADVERSE REACTIONS The following adverse reactions are discussed in greater detail in other sections of the labeling:

Cardiovascular Thrombotic Events (see WARNINGS)

GI Bleeding, Ulceration and Perforation (see WARNINGS)

Hepatotoxicity (see WARNINGS)

Hypertension (see WARNINGS)

Heart Failure and Edema (see WARNINGS)

Renal Toxicity and Hyperkalemia (see WARNINGS)

Anaphylactic Reactions (see WARNINGS)

Serious Skin Reactions (see WARNINGS)

Hematologic Toxicity (see WARNINGS) 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. In 718 patients treated for shorter periods, i.e., 2 weeks or less, with diclofenac potassium tablets, adverse reactions were reported one-half to one-tenth as frequently as by patients treated for longer periods. In a 6-month, double-blind trial comparing diclofenac potassium tablets (N = 196) versus diclofenac sodium delayed-release tablets (N = 197) versus ibuprofen (N = 197), adverse reactions were similar in nature and frequency. In patients taking diclofenac potassium tablets or other NSAIDs, the most frequently reported adverse experiences occurring in approximately 1%-10% of patients are: Gastrointestinal experiences including: abdominal pain, constipation, diarrhea, dyspepsia, flatulence, gross bleeding/perforation, heartburn, nausea, GI ulcers (gastric/duodenal) and vomiting. Abnormal renal function, anemia, dizziness, edema, elevated liver enzymes, headaches, increased bleeding time, pruritus, rash and tinnitus. Additional adverse experiences reported occasionally include: Body as a Whole: fever, infection, sepsis Cardiovascular System: congestive heart failure, hypertension, tachycardia, syncope Digestive System: dry mouth, esophagitis, gastric/peptic ulcers, gastritis, gastrointestinal bleeding, glossitis, hematemesis, hepatitis, jaundice Hemic and Lymphatic System: ecchymosis, eosinophilia, leukopenia, melena, purpura, rectal bleeding, stomatitis, thrombocytopenia Metabolic and Nutritional: weight changes Nervous System: anxiety, asthenia, confusion, depression, dream abnormalities, drowsiness, insomnia, malaise, nervousness, paresthesia, somnolence, tremors, vertigo Respiratory System: asthma, dyspnea Skin and Appendages: alopecia, photosensitivity, sweating increased Special Senses: blurred vision Urogenital System: cystitis, dysuria, hematuria, interstitial nephritis, oliguria/polyuria, proteinuria, renal failure Other adverse reactions, which occur rarely are: Body as a Whole: anaphylactic reactions, appetite changes, death Cardiovascular System: arrhythmia, hypotension, myocardial infarction, palpitations, vasculitis Digestive System: colitis eructation, fulminant hepatitis with and without jaundice, liver failure, liver necrosis, pancreatitis Hemic and Lymphatic System: agranulocytosis, hemolytic anemia, aplastic anemia, lymphadenopathy, pancytopenia Metabolic and Nutritional: hyperglycemia Nervous System: convulsions, coma, hallucinations, meningitis Respiratory System: respiratory depression, pneumonia Skin and Appendages: angioedema, toxic epidermal necrolysis, erythema multiforme, exfoliative dermatitis, Stevens-Johnson Syndrome, urticaria Special Senses: conjunctivitis, hearing impairment

Warnings and Precautions

WARNINGS 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: Gastrointestinal Bleeding, Ulceration, and Perforation). 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 10-14 days following CABG surgery found an increased incidence of myocardial infarction and stroke. NSAIDs are contraindicated in the setting of CABG (see CONTRAINDICATIONS) . Post-MI Patients Observational studies conducted in the Danish National Registry have demonstrated that patients treated with NSAIDs in the post-MI period were at increased risk of reinfarction, CV-related death, and all-cause mortality beginning in the first week of treatment. In this same cohort, the incidence of death in the first year post-MI was 20 per 100 person years in NSAID-treated patients compared to 12 per 100 person years in non-NSAID exposed patients. Although the absolute rate of death declined somewhat after the first year post-MI, the increased relative risk of death in NSAID users persisted over at least the next four years of follow-up. Avoid the use of diclofenac potassium tablets in patients with a recent MI unless the benefits are expected to outweigh the risk of recurrent CV thrombotic events. If diclofenac potassium tablets are used in patients with a recent MI, monitor patients for signs...

Drug Interactions

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 potassium tablets 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: Hematological Toxicity). Aspirin Clinical Impact: Controlled clinical studies showed that the concomitant use of NSAIDs and analgesic doses of aspirin does not produce any greater therapeutic effect than the use of NSAIDs alone. In a clinical study, the concomitant use of an NSAID and aspirin was associated with a significantly increased incidence of GI adverse reactions as compared to use of the NSAID alone (see WARNINGS: Gastrointestinal Bleeding, Ulceration, and Perforation). Intervention: Concomitant use of diclofenac potassium tablets and analgesic doses of aspirin is not generally recommended because of the increased risk of bleeding (see WARNINGS: Hematological Toxicity). Diclofenac potassium tablets are 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 potassium tablets and ACE-inhibitors, ARBs, or beta-blockers, monitor blood pressure to ensure that the desired blood pressure is obtained.

During concomitant use of diclofenac potassium tablets and ACE-inhibitors or ARBs in patients who are elderly, volume-depleted, or have impaired renal function, monitor for signs of worsening renal function (see WARNINGS: Renal Toxicity and Hyperkalemia).

When these drugs are administered concomitantly, patients should be adequately hydrated. Assess renal function at the beginning of the concomitant treatment and periodically thereafter....

Contraindications

CONTRAINDICATIONS Diclofenac potassium tablets are 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: Anaphylactic Reactions, Serious Skin Reactions).

History of asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDs. Severe, sometimes fatal, anaphylactic reactions to NSAIDs have been reported in such patients (see WARNINGS: Anaphylactic Reactions, Exacerbation of Asthma Related to Aspirin Sensitivity).

In the setting of coronary artery bypass graft (CABG) surgery (see WARNINGS: Cardiovascular Thrombotic Events).

Pregnancy and Breastfeeding

Pregnancy Risk Summary Use of NSAIDs, including diclofenac potassium tablets, 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 potassium tablets use between about 20 and 30 weeks of gestation, and avoid diclofenac potassium tablets use at about 30 weeks of gestation and later in pregnancy (see WARNINGS: Fetal Toxicity). Premature Closure of Fetal Ductus Arteriosus Use of NSAIDs, including diclofenac potassium tablets, at about 30 weeks gestation or later in pregnancy increases the risk of premature closure of 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 teratogenicity was observed in mice, rats, or rabbits given diclofenac during the period of organogenesis at doses up to approximately 0.5, 0.5, and 1 times, respectively, the maximum recommended human dose (MRHD) of diclofenac potassium tablets, 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...

Nursing Mothers Risk Summary Based on available data, diclofenac may be present in human milk. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for diclofenac potassium tablets and any potential adverse effects on the breastfed infant from the diclofenac potassium tablets or from the underlying maternal condition. Data One woman treated orally with a diclofenac salt, 150 mg/day, had a milk diclofenac level of 100 mcg/L, equivalent to an infant dose of about 0.03 mg/kg/day. Diclofenac was not detectable in breast milk in 12 women using diclofenac (after either 100 mg/day orally for 7 days or a single 50 mg intramuscular dose administered in the immediate postpartum period).

Overdosage

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: Cardiovascular Thrombotic Events, Gastrointestinal Bleeding, Ulceration, and Perforation, Hypertension, Renal Toxicity and Hyperkalemia). Manage patients with symptomatic and supportive care following an NSAID overdosage. There are no specific antidotes. Consider emesis and/or 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 in patients with a large overdose (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).

How Supplied

HOW SUPPLIED Diclofenac Potassium Tablets, USP are available containing 50 mg of diclofenac potassium, USP. The 50 mg tablets are white, film-coated, round, unscored tablets debossed with M over D5 on one side of the tablet and blank on the other side. They are available as follows: NDC 10135-0806-01 bottles of 100 tablets Store at 20° to 25°C (68° to 77°F). [See USP Controlled Room Temperature.] Protect from moisture. Dispense in a tight, light-resistant container as defined in the USP using a child-resistant closure. PHARMACIST: Dispense a Medication Guide with each prescription. Revised: 03/2025

About This Information

This drug information is sourced from FDA-approved labeling via the openFDA database. It is intended for educational and reference purposes only. This is not medical advice. Always consult your healthcare provider before making decisions about medication. Drug information may be updated by the FDA; check with your pharmacist for the most current information.

What are side effects?

Side effects are unwanted reactions that can occur when taking a medication. They range from mild (headache, nausea) to severe (allergic reactions, organ damage). Not everyone experiences side effects, and severity varies. Report any concerning side effects to your doctor.

What are drug interactions?

Drug interactions occur when a medication is affected by another drug, food, or supplement. Interactions can make medications less effective or cause dangerous side effects. Always tell your doctor about all medications and supplements you take.