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What does it do?

Diclofenac is an anti-inflammatory medicine used to reduce pain and inflammation.

Before you start

  • Tell your doctor if you have heart, kidney, liver, stomach or bowel problems, high blood pressure, asthma, or if you have ever had a stroke or TIA (mini-stroke).
  • Tell your doctor if you have had problems with aspirin or other anti-inflammatory medicines.
  • Tell your doctor if you are pregnant, planning to become pregnant, or breastfeeding.

How should you take it?

Take diclofenac as directed.
Tablet or capsule: Take with a large glass of water.
Coated or slow-release tablet: Take with a large glass of water. Swallow whole - do not crush or chew.
Dispersible tablet: Dissolve in water before taking.
Suppository: Remove the wrapper before inserting into the rectum.

What if you forget a dose?

If you take diclofenac regularly and it is nearly time for your next dose, skip the missed dose and take your next dose at the usual time. Otherwise, take the missed dose as soon as you remember. Do not take two doses at the same time.

Can you take other medicines?

Some medicines available without a prescription may react with diclofenac including:

  • anti-inflammatories, such as ibuprofen (e.g. Nurofen®), or aspirin (e.g. Disprin®, in doses used for pain relief). These can also be found in some cold and flu medicines (e.g. Nurofen Cold and Flu®), and creams or gels (e.g. Voltaren Emulgel®)
  • low-dose aspirin (e.g. Cartia®)

Tell your pharmacist or doctor about all medicines or treatments that you may be taking, including vitamins, herbal products or recreational drugs.

What side effects might you notice?

Side EffectsRecommended action

Symptoms of allergy including: skin rash, itching, swelling, trouble breathing

Symptoms of a peptic ulcer including: tummy pain, red or black bowel motions, vomit that looks like coffee grounds

Symptoms of liver problems including: yellow skin or eyes, itching, dark urine, pale bowel motions, abdominal pain

Tell your doctor immediately

Swollen feet or legs, short of breath

Tell your doctor

Anal irritation with suppository use

Tell your doctor if troublesome

Indigestion, nausea, diarrhoea

Take with food and tell your doctor if symptoms continue

If you notice any other effects, discuss them with your doctor or pharmacist.

Other information:

  • It is safe to take both paracetamol and anti-inflammatory medicines for pain relief if you need to.
  • Anti-inflammatory medicines can sometimes cause kidney problems, especially in people who are dehydrated. Don’t take diclofenac if you are dehydrated.
  • Long-term use of anti-inflammatory medicines may increase the chances of a heart attack or stroke – talk to your health professional about your risk.

This leaflet contains important, but not all, information about this medicine.

Prepared by the MyMedicines Committee at Christchurch Hospital, Te Whatu Ora - Waitaha, New Zealand. April 2024

For more general information about this sheet and its contents, see: What does a My Medicines sheet cover?

About My Medicines

My Medicines Patient Information Leaflets (PILs) contain important, but not all, information about the medicines they describe.

For more information about the sheets, see: What does a My Medicines sheet cover?

My Medicines is developed by a team at Te Whatu Ora – Waitaha. Our team is made up of doctors, pharmacists, and a non-medical person to help us keep to plain language. We also discuss our information with specialist health professionals or groups when needed