Diclofenac

Sodium DR: osteoarthritis, rheumatoid arthritis and ankylosing spondylitis. Sodium ER: OA/RA. Cambia: acute migraine with or without aura at age ≥18, not prevention or established cluster-headache treatment. Zipsor: mild/moderate acute pain at age ≥12. Discontinued Zorvolex brand’s older label: adult acute pain and OA pain.

OTC Voltaren Arthritis Pain gel: temporary arthritis pain only in hand, wrist, elbow, foot, ankle or knee; not strains/sprains/bruises, back/hip/shoulder or immediate relief. Selected 1.5%/2% solutions treat knee OA. Flector treats acute pain from minor strains, sprains and contusions at age ≥6.

Apply gel/solutions only to clean, dry, intact skin; avoid eyes/mucosa, external heat and occlusive dressings. OTC gel: no bandage or another product at the same site. Solutions: no bathing/showering for ≥30 minutes; let dry before clothing, other topical products or skin contact, and protect treated knees from sunlight. Flector: remove for bathing/showering; tape loose edges or use breathable mesh if needed. Do not combine oral/topical NSAIDs unless prescribed after benefit/risk review with appropriate monitoring. Other oral salt/release products, ocular/injectable/actinic-keratosis and combination products need separate labels.

Prescription products: diclofenac/component hypersensitivity, aspirin/NSAID-associated asthma/urticaria/allergic reactions and CABG setting. Zipsor additionally contraindicates bovine-protein hypersensitivity because of gelatin. Flector additionally contraindicates non-intact/damaged skin. OTC gel: do not use after allergy to any pain reliever/fever reducer, immediately before/after heart surgery, in eyes/nose/mouth or for excluded injury sites.

Reviewed prescription oral and topical NSAID labels warn of potentially fatal MI/stroke and GI bleeding, ulceration or perforation. CV risk may begin early and increase with duration. GI events can occur without warning; prior ulcer/bleeding and older age raise risk. Prescription products are contraindicated in CABG. OTC Voltaren uses Drug Facts heart/stroke and stomach-bleeding warnings rather than a prescription boxed-warning panel.

Oral products commonly cause GI symptoms, dizziness/headache, edema and abnormal liver/renal tests. Cambia trials prominently report nausea and dizziness. Topicals can cause local dryness, dermatitis, itching or burning. Serious systemic events remain possible. Overdose/ingestion of topical products requires poison-center/emergency assessment; no specific antidote is known and dialysis may be ineffective because of protein binding.

• Other NSAIDs/salicylates add GI toxicity with little extra efficacy and are not recommended. Aspirin does not eliminate CV risk; analgesic-dose co-use increases bleeding. Do not stop prescribed low-dose aspirin without advice.
• Anticoagulants, antiplatelets, SSRIs/SNRIs and corticosteroids increase bleeding risk; monitor.
• ACE inhibitors/ARBs/beta blockers and diuretics may work less well; assess BP, hydration, renal function and diuretic response.
• Monitor digoxin concentrations, lithium toxicity, methotrexate toxicity and cyclosporine-associated renal effects.
• CYP2C9 inhibitors such as voriconazole increase exposure; inducers such as rifampin can reduce efficacy. Dose review may be needed.
• Pemetrexed requires an oncology-directed NSAID interruption/monitoring plan, especially CrCl 45–79 mL/min. Do not independently apply a generalized interval.

Cambia labeling cautions against nonprescription acetaminophen-containing products during use because of additive liver concerns. OTC gel advises clinician/pharmacist review with other medicines; topical delivery does not make interacting medicines irrelevant.

Current prescription labels limit use at about 20–30 weeks to the lowest dose/shortest duration only when necessary and avoid use at about ≥30 weeks. Fetal kidney dysfunction/oligohydramnios can begin around 20 weeks; consider fluid ultrasound if treatment exceeds 48 hours and stop if oligohydramnios occurs. OTC gel advises avoiding ≥20 weeks unless definitely doctor directed. Diclofenac may enter milk; weigh maternal need and infant risk. NSAID-related ovulation delay may be reversible; consider withdrawal during infertility evaluation.

Zipsor acute-pain labeling begins at 12; Flector at 6. Other reviewed prescription products have no established pediatric use; OTC gel requires doctor review under 18. Older adults have higher CV/GI/renal risk. No universal renal/hepatic dose table applies: avoid advanced-renal use unless carefully justified; hepatic disease may require reduced oral doses. Cambia has insufficient hepatic dosing information; Zipsor/Zorvolex direct lowest-dose use and discontinuation if ineffective. Legacy product wording is not used to override current class fetal-risk guidance.

Diclofenac inhibits COX-1/COX-2 and prostaglandin synthesis, producing analgesic, anti-inflammatory and antipyretic effects. Oral first-pass metabolism limits systemic availability; predominantly CYP2C9 oxidation followed by conjugation and urinary/biliary excretion. Topical products still produce measurable systemic exposure; heating/occlusion can change application conditions and should be avoided.

Protein binding

More than 99%.

ER label terminal half-life

About 2 hours; ER absorption timing differs from elimination.

Formulation rule

Same milligram strength does not establish equivalent exposure or interchangeable dosing.

• Assess GI bleeding/ulcer history, CV disease, BP, edema, hydration, renal function/potassium, liver disease and interacting medicines.
• For long-term prescription use, consider periodic CBC/chemistry. Transaminases at baseline and periodically; label suggests within 4–8 weeks after initiation, with later timing individualized.
• Stop and assess liver symptoms or persistent/worsening tests, rash/systemic hypersensitivity, bleeding or renal deterioration.
• Review topical site reactions and exact amount/frequency; OTC gel stops at no relief by7 days or pain persisting beyond21 days unless clinician directed.

Do not substitute diclofenac products or add another NSAID. Seek urgent care for chest pain, focal weakness, breathing trouble, black stools, bloody vomit or severe allergy. Report jaundice, dark urine, fever/rash, edema or reduced urination. Keep gel/solution away from eyes and mouth; wash hands after application/handling as directed. Fold used Flector systems so adhesive sides stick together and discard safely away from children/pets. Discuss pregnancy, breastfeeding and any OTC pain medicine.

Ingredient / route

Diclofenac potassium · oral liquid-filled capsule.

Appearance / imprint

Translucent pale yellow; X592 in black.

Distributor

Assertio Specialty Pharmaceuticals.

Example NDC

82497-008-12 · bottle of 120.

U.S. status

Prescription; topical Voltaren Arthritis Pain is OTC.

Selected sodium tablets

DR 50/75 mg supplied in selected label; ER 100 mg.

Selected oral potassium products

Cambia 50 mg packet; Zipsor 25 mg capsule.

Discontinued Zorvolex brand

FDA lists 18/35 mg free-acid capsules as discontinued; older label retained for formulation context.

Selected topicals

OTC sodium gel1%; sodium solution1.5% drops /2% pump; epolamine1.3% Flector system.

Scope limits

Other oral tablets, injected, ophthalmic, 3% dermatologic, combination products and non-U.S. regimens require their own labels. FDA lists Pennsaid 2% brand as discontinued; selected generic 2% solution is reviewed separately.

Use each exact label. Selected ER: 20–25°C, protect light/moisture; DR:25°C, excursions15–30°C, moisture protection. Cambia:25°C, excursions15–30°C. Zipsor/Zorvolex/2% solution/Flector:20–25°C, excursions15–30°C; protect capsules from moisture and keep Flector envelopes sealed. OTC gel:20–25°C, do not freeze; retain dosing card/user guide. Legacy1.5% storage should follow its exact dispensed package.