Diclofenac

Diclofenac is a nonsteroidal anti-inflammatory drug (NSAID) used to relieve pain, swelling, and inflammation in conditions such as arthritis, muscle injuries, and menstrual cramps. Diclofenac is used for Post-operative pain (select formulations), Inflammatory conditions and Pain management.

Also called: Xiclo (United States) · Voltarol (United Kingdom) · Pennsaid (Canada) · Fenac (Australia) · Difenax (Philippines)

Pronunciation: (dye-KLOE-fen-ak).

Generic name
Diclofenac
Brand names
Voveran, Diclogesic, Motifene, Diclac, Voltarol, Rheuma-Plex
Drug class
Nonsteroidal Anti-Inflammatory Drug (NSAID)

Availability and supply rules vary by country

Trade names by country: United States · United Kingdom · Canada · Australia · India · Nepal · New Zealand

Australia: Voltaren, Fenac EC, DICLOFENAC-WGR, Diclofenac Sandoz, Clonac, Dofidaz, Solaraze · Full directory

What Diclofenac is and how it works

Diclofenac is a nonsteroidal anti-inflammatory drug (NSAID) used to relieve pain, swelling, and inflammation in conditions such as arthritis, muscle injuries, and menstrual cramps. It is also available in topical forms for localized pain relief, such as joint or muscle pain. Diclofenac works by blocking substances in the body (prostaglandins) that cause inflammation and pain. It can be taken orally, applied to the skin, or used as an injection or suppository, depending on the condition being treated. Key points: Use the lowest effective dose for the shortest possible time. Diclofenac may increase the risk of serious heart or stomach problems, especially with long-term use. Always follow your healthcare provider's instructions. (1) (3)

Uses, formulations, monitoring, and supply rules can differ by patient, product, and country. Follow the exact local product information and professional advice.

Mechanism of action: how Diclofenac works

Diclofenac is classified as Nonsteroidal Anti-Inflammatory Drug (NSAID). See the how-to-take, warnings, and interactions sections for the redistributed clinician-authored dosing and safety detail formerly held in this field. (2) (3)

What is Diclofenac used for?

Post-operative pain (select formulations)

Post-operative pain (select formulations) (1) (3)

Inflammatory conditions

Inflammatory conditions (1) (3)

Osteoarthritis and rheumatoid arthritis pain and inflammation

Osteoarthritis and rheumatoid arthritis pain and inflammation (1) (3)

Pain management

Pain management (1) (3)

Primary dysmenorrhea

Primary dysmenorrhea (1) (3)

Ankylosing spondylitis

Ankylosing spondylitis (1) (3)

Acute musculoskeletal injury

Acute musculoskeletal injury (1) (3)

Before taking Diclofenac

Do not take / not appropriate for

  • Do not take diclofenac if you have a known hypersensitivity to diclofenac or to any component of the product — for example a previous anaphylactic reaction or serious skin reaction. The FDA-approved label lists this as an absolute contraindication. (all countries) (3) (1)
  • Do not take diclofenac if you have a history of asthma, urticaria (hives), or other allergic-type reactions after taking aspirin or any other NSAID. Severe, sometimes fatal, anaphylactic reactions to NSAIDs have been reported in such patients. (all countries) (3)
  • Do not take diclofenac for pain around the time of coronary artery bypass graft (CABG) heart surgery. It is contraindicated in the setting of CABG surgery because of the increased risk of heart attack and stroke, and it should not be taken right before or right after that surgery. (all countries) (3) (1)
  • Diclofenac is not appropriate if you have active gastrointestinal bleeding or an active or previous peptic ulcer or perforation of the stomach or intestines. NSAIDs including diclofenac carry a boxed warning for serious gastrointestinal bleeding, ulceration, and perforation, which can be fatal and can occur without warning symptoms; tell your doctor before taking diclofenac if you have ever had stomach ulcers or bleeding in the stomach or intestines. (all countries) (3)
  • Do not take diclofenac if you have severe heart failure unless a doctor has specifically decided the benefit outweighs the risk. The FDA label directs that use be avoided in severe heart failure unless the benefits are expected to outweigh the risk of worsening heart failure, and NHS guidance directs anyone with heart failure to speak to a doctor before taking it. (all countries)
  • Do not take diclofenac if you have severe or advanced kidney disease unless a doctor has judged the expected benefit to outweigh the risk of worsening kidney function, with monitoring. Diclofenac is described as contraindicated in renal insufficiency because of reduced kidney blood flow, and the FDA label directs that it be avoided in advanced renal disease. (all countries) (3)
  • Do not take diclofenac if you have severe liver disease without first speaking to a doctor. Hepatic metabolism accounts for almost all of diclofenac's elimination, so people with liver disease may need a reduced dose, severe hepatotoxicity can develop without warning symptoms, and NHS guidance directs anyone with severe liver disease to check with a doctor before taking it. (all countries)
  • Do not take diclofenac at or after about 20 weeks of pregnancy, including the third trimester, unless your doctor specifically tells you to. NSAID use from about 20 weeks can cause fetal kidney problems, and use at about 30 weeks and later risks premature closure of the fetal ductus arteriosus. (all countries) (1)

Tell your clinician about

  • Any allergy to diclofenac, aspirin, or another NSAID, or past NSAID side effects such as wheezing, a runny nose, rash, or swelling of the skin.
  • Asthma, especially with frequent nasal congestion, a runny nose, or nasal polyps.
  • Any past stomach ulcer, bleeding in the stomach or intestines, or a perforation.
  • Heart disease, a previous heart attack or stroke, heart failure, or high blood pressure.
  • Kidney disease or liver disease.
  • Crohn's disease, ulcerative colitis, lupus, or a blood clotting disorder.
  • Pregnancy, plans for pregnancy, or breastfeeding.
  • Any planned surgery, especially coronary artery bypass graft (CABG) surgery.
(3) (1)

Diclofenac dosage and how to take it

  • Take diclofenac exactly as prescribed. Do not exceed the recommended dose or duration. Take oral forms with food or milk to reduce stomach upset. Swallow tablets whole with water. Do not crush or chew extended-release forms. For topical use, apply to clean, dry skin and wash hands after application.
  • This page does not provide a dose calculator. Dosing must follow the prescriber, pharmacist, or product label.
(1) (3)

Procedures and treatment changes

Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (3)

Missed dose

If you miss a dose, take it as soon as you remember. If it is almost time for your next scheduled dose, skip the missed dose — do not take a double dose to make up for it. If you are unsure, contact your prescriber or pharmacist for advice.

Overdose

Symptoms of overdose may include severe stomach pain, vomiting, drowsiness, difficulty breathing, or seizures. Seek emergency medical attention or call your local poison control center immediately. (1) (3)

Diclofenac side effects

Side effects and their urgency vary; report severe, persistent, or concerning symptoms to a healthcare professional.

Stomach pain

Incidence: Reported in the clinician-authored database; frequency not established

Nausea

Incidence: Reported in the clinician-authored database; frequency not established

Indigestion

Incidence: Reported in the clinician-authored database; frequency not established

Diarrhea

Incidence: Reported in the clinician-authored database; frequency not established

Heart attack

Incidence: Reported in the clinician-authored database; seek prompt medical attention if this occurs

Stroke

Incidence: Reported in the clinician-authored database; seek prompt medical attention if this occurs

Gastrointestinal bleeding

Incidence: Reported in the clinician-authored database; seek prompt medical attention if this occurs

Kidney problems

Incidence: Reported in the clinician-authored database; seek prompt medical attention if this occurs

Chest pain, difficulty breathing, sudden weakness or numbness, severe allergic reaction (swelling, rash, trouble breathing), vomiting blood, or severe skin reaction

Incidence: Reported in the clinician-authored database; seek immediate medical attention if this occurs

Serious warnings

FDA BOXED WARNING — Cardiovascular thrombotic events — serious

Symptoms: FDA BOXED WARNING — Cardiovascular thrombotic events: NSAIDs including diclofenac 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. Diclofenac is contraindicated for the treatment of peri-operative pain in the setting of coronary artery bypass graft (CABG) surgery. Gastrointestinal bleeding, ulceration, and perforation: NSAIDs including diclofenac cause an increased risk of serious gastrointestinal 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 gastrointestinal bleeding are at greater risk. Use the lowest effective dose for the shortest duration necessary. Monitor blood pressure, renal function, and for signs of gastrointestinal bleeding.

Action: Follow the urgency stated and seek prompt or emergency care when indicated. (2) (3)

A history of allergic reaction to NSAIDs (such as aspirin or ibuprofen), active stomach or intestinal ulcers, recent heart bypass surgery (CABG) or a recent heart attack, severe liver or kidney disease, or uncontrolled heart failure all need urgent assessment by a prescriber or clinician before diclofenac is used — serious

Symptoms: A history of allergic reaction to NSAIDs (such as aspirin or ibuprofen), active stomach or intestinal ulcers, recent heart bypass surgery (CABG) or a recent heart attack, severe liver or kidney disease, or uncontrolled heart failure all need urgent assessment by a prescriber or clinician before diclofenac is used; the clinician will decide whether it is appropriate.

Action: Follow the urgency stated and seek prompt or emergency care when indicated. (2) (1)

May increase risk of heart attack or stroke, especially with long-term use — serious

Symptoms: May increase risk of heart attack or stroke, especially with long-term use.

Action: Follow the urgency stated and seek prompt or emergency care when indicated. (1) (3)

Can cause serious stomach or intestinal bleeding, ulcers, or perforation — serious

Symptoms: Can cause serious stomach or intestinal bleeding, ulcers, or perforation.

Action: Follow the urgency stated and seek prompt or emergency care when indicated. (1) (3)

Use with caution in patients with kidney or liver impairment — serious

Symptoms: Use with caution in patients with kidney or liver impairment.

Action: Follow the urgency stated and seek prompt or emergency care when indicated. (1) (3)

Not recommended during late pregnancy (third trimester) — serious

Symptoms: Not recommended during late pregnancy (third trimester).

Action: Follow the urgency stated and seek prompt or emergency care when indicated. (1) (3)

May cause severe skin reactions or allergic reactions — serious

Symptoms: May cause severe skin reactions or allergic reactions.

Action: Follow the urgency stated and seek prompt or emergency care when indicated. (1) (3)

Interactions

Medicine or testEffectAction
GeneralReduces the antihypertensive effect of ACE inhibitors, ARBs, and diuretics (2)
GeneralIncreased nephrotoxicity risk with other NSAIDs, ciclosporin, or tacrolimus (2) (1)
GeneralRaises lithium and methotrexate blood levels (2)
GeneralIncreases bleeding risk with anticoagulants and antiplatelet agents (2) (1)
SSRIs and SNRIs (e.g., citalopram, fluoxetine, sertraline, duloxetine, venlafaxine)Combined use with diclofenac may further increase bleeding risk; discuss with the prescriber or pharmacist before starting or changing either medicine. (1)
General (DB narrative)Diclofenac may interact with blood thinners (e.g., warfarin), other NSAIDs, corticosteroids, certain blood pressure medications (ACE inhibitors, ARBs), lithium, methotrexate, and some antidepressants. Always inform your healthcare provider about all medicines and supplements you are taking. (2)

Pregnancy, breastfeeding, kidney/liver function, age

Pregnancy

Recorded pregnancy category: there is a risk of fetal renal dysfunction after 20 weeks of pregnancy and of premature closure of the ductus arteriosus in the third trimester. Discuss use with your doctor before taking diclofenac at any stage of pregnancy, and especially at or after 20 weeks, so the doctor can weigh the risks and benefits. (Corroborated: MedlinePlus similarly advises not taking diclofenac at or after 20 weeks of pregnancy unless a doctor directs otherwise.) (1) (3)

Breastfeeding

The FDA label for diclofenac sodium delayed-release tablets notes that diclofenac is present in human breast milk at low, variable levels; because of the potential for serious NSAID-related adverse reactions in a nursing infant, a decision should be made to discontinue breastfeeding or discontinue diclofenac, taking into account the importance of the drug to the mother — discuss this with your prescriber. (1) (3)

Children

Diclofenac is not routinely recommended for children except under specialist supervision. Dosing is weight-based and condition-specific. (1) (3)

Renal Impairment

FDA label guidance: no dosage adjustment is needed for mild-to-moderate renal impairment, but diclofenac should be avoided in advanced renal disease unless the anticipated benefits outweigh the risk of worsening renal function, and renal function should be monitored. Because hepatic metabolism accounts for almost all of diclofenac's elimination, patients with hepatic impairment may need a reduced dose, and liver enzymes should be monitored (e.g., within 4-8 weeks of starting treatment) — this should be individualized by the prescriber. (1) (3)

Hepatic Impairment

FDA label guidance: no dosage adjustment is needed for mild-to-moderate renal impairment, but diclofenac should be avoided in advanced renal disease unless the anticipated benefits outweigh the risk of worsening renal function, and renal function should be monitored. Because hepatic metabolism accounts for almost all of diclofenac's elimination, patients with hepatic impairment may need a reduced dose, and liver enzymes should be monitored (e.g., within 4-8 weeks of starting treatment) — this should be individualized by the prescriber. (1) (3)

Monitoring

(1) (3)

Storage

Store at room temperature away from moisture and heat, in the original container, tightly closed, and out of reach of children (not in the bathroom). Dispose of unused medicine via a medicine take-back program rather than household trash.

Study the drug class: NSAIDs, including COX-2 selective agents (practice MCQs)

Professional information

Clinician-facing context only. This section does not replace current product labeling.

General

Indication: Post-operative pain (select formulations)

Dose summary: Osteoarthritis: 100-150 mg/day in divided doses (e.g., 50 mg 2-3 times daily, or 75 mg twice daily). Rheumatoid arthritis: 150-200 mg/day in divided doses (e.g., 50 mg 3-4 times daily, or 75 mg twice daily). Ankylosing spondylitis: 100-125 mg/day (25 mg four times daily, plus an extra 25 mg at bedtime if needed). Topical gel: apply as directed to the affected area. Use the lowest effective dose for the shortest duration.

Renal context: FDA label: no dosage adjustment is needed for patients with mild-to-moderate renal impairment; diclofenac should be avoided in patients with advanced renal disease unless the anticipated benefits are expected to outweigh the risk of worsening renal function, and renal function should be monitored in patients with renal impairment. (2) (3)

Mechanism of action

Hepatic guidance

FDA label: hepatic metabolism accounts for approximately 50% or more of diclofenac's elimination; patients with hepatic impairment may require a reduced dose. Because severe hepatotoxicity (including fatal hepatitis) can occur, patients should be told the signs/symptoms of hepatotoxicity, and liver enzymes should be monitored periodically (e.g., within 4-8 weeks of starting treatment) during long-term therapy; if abnormal liver tests persist or worsen, or if clinical signs/symptoms of liver disease develop, seek medical advice promptly and let the prescriber decide whether to continue or stop diclofenac.

Frequently asked questions

What conditions does diclofenac treat?

Diclofenac is used to relieve pain and inflammation in conditions such as osteoarthritis, rheumatoid arthritis, ankylosing spondylitis, acute musculoskeletal injuries, and menstrual pain. Topical forms are used for localized joint or muscle pain.

How quickly does diclofenac work?

Oral diclofenac usually begins to relieve pain within 30 to 60 minutes. Topical forms may take several days to achieve full effect.

Can I take diclofenac with other painkillers?

Ask your prescriber or pharmacist which additional pain medicines are appropriate. Diclofenac is generally not combined with other NSAIDs (such as ibuprofen or naproxen) because of added interaction and side-effect risk, so confirm with a clinician before combining diclofenac with any other pain medicine, including acetaminophen (paracetamol).

Is diclofenac safe in pregnancy or breastfeeding?

Diclofenac is not recommended during the third trimester of pregnancy due to risk of fetal harm. Use during breastfeeding should be discussed with your healthcare provider.

What should I do if I develop stomach pain while taking diclofenac?

Seek medical attention promptly if you develop severe stomach pain, black or bloody stools, or vomiting blood, and let the clinician advise on whether to continue or stop diclofenac.

Can diclofenac cause high blood pressure?

Yes, diclofenac and other NSAIDs may increase blood pressure or worsen existing hypertension. Regular monitoring is recommended.

How long can I safely use diclofenac?

Use diclofenac at the lowest effective dose for the shortest duration necessary. Long-term use increases the risk of serious side effects.

What is the mechanism of action of Diclofenac?

Diclofenac is classified as Nonsteroidal Anti-Inflammatory Drug (NSAID). See the how-to-take, warnings, and interactions sections for the redistributed clinician-authored dosing and safety detail formerly held in this field. (2) (3)

What is the generic name of Diclofenac?

The generic name is Diclofenac. It is sold under brand names including Voveran, Diclogesic, Motifene, Diclac, Voltarol, Rheuma-Plex.

What class of drug is Diclofenac?

Diclofenac is classed as: Nonsteroidal Anti-Inflammatory Drug (NSAID).

References

  1. Diclofenac: MedlinePlus Drug InformationU.S. National Library of Medicine, MedlinePlus · United States · accessed 2026-08-06 · source 1
  2. Diclofenac — MedGuideGlobal Medicines Database RecordMedGuideGlobal clinician-authored medicine record · Not specified · accessed 2026-08-06 · source 2
  3. DailyMed — DICLOFENAC SODIUM Delayed-Release Tablets, FDA-approved labeling (PD-Rx Pharmaceuticals, setid 681b6b25-4a28-44f2-8042-d5e01a502116)U.S. Food and Drug Administration (via DailyMed) · United States · accessed 2026-08-07 · source 3
  4. DICLOFENAC SODIUM TABLET, DELAYED RELEASE [ACTAVIS PHARMA, INC.] — US prescribing information (DailyMed SPL)U.S. National Library of Medicine (DailyMed) · US · accessed 2026-08-14 · source 4
  5. Diclofenac Sodium — FDA approval record (Drugs@FDA ANDA211253)U.S. Food and Drug Administration · US · accessed 2026-08-14 · source 5
  6. Diclofenac — RxNorm normalized drug concept (RXCUI 3355)U.S. National Library of Medicine (RxNorm) · US · accessed 2026-08-14 · source 6

Brand names by country

Single-ingredient Diclofenac names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.

Priority countries

United States

India

Source-listed products; local stock and regulatory approval have not been confirmed. Check the exact ingredient, strength, and formulation with a pharmacist.

  • Reactin 100 SR TabletTablet PR · 100mg · Cipla Ltdpharmacy source recorded · checked 2026-09-24
  • Zeldinac 100 Tablet SRTablet SR · 100mg · Leeford Healthcare Ltdpharmacy source recorded · checked 2026-09-24
  • Zeldinac Transdermal PatchTransdermal Patch · 200mg · Leeford Healthcare Ltdpharmacy source recorded · checked 2026-09-24
  • Dikloflame InjectionInjection · 25mg · Intas Pharmaceuticals Ltdpharmacy source recorded · checked 2026-09-24
  • Diklotas 25mg InjectionInjection · 25mg · Intas Pharmaceuticals Ltdpharmacy source recorded · checked 2026-09-24
  • Aldigesic InjectionInjection · 75mg · Alkem Laboratories Ltdpharmacy source recorded · checked 2026-09-24
  • Vovedic InjectionInjection · 75mg · Leeford Healthcare Ltdpharmacy source recorded · checked 2026-09-24
  • Powerflam InjectionInjection · NA · Alkem Laboratories Ltdpharmacy source recorded · checked 2026-09-24

Nepal

Source-listed products; local stock and regulatory approval have not been confirmed. Check the exact ingredient, strength, and formulation with a pharmacist.

  • A FenacInjection · 75mg · Acme Laboratories Ltdreference source · checked 2026-09-24
  • Atune DTTablet · 50mg · Panas Pharmaceutical Pvt. Ltd.reference source · checked 2026-09-24
  • C NacTablet · 50mg · Chemi Drug Industries Pvt. Ltd.reference source · checked 2026-09-24
  • CerinCapsule · 50mg · Maruti Pharma Pvt. Ltd.reference source · checked 2026-09-24
  • ClofenacTablet · 50mg · Square Pharmaceuticals Ltd.reference source · checked 2026-09-24
  • ClonacGel · 1% · Curex Pharmaceuticals Pvt. Ltd.reference source · checked 2026-09-24
  • DackTablet · 50mg · Magnus Pharma Pvt. Ltd.reference source · checked 2026-09-24
  • DiacerTablet · 50mg · Apex Pharmaceuticals Pvt. Ltd.reference source · checked 2026-09-24
View brands in additional countries.

Philippines

Voltaren, Difenax, Neo Pyrazon

Related medicines

Compare within this class

More medicines A–Z