Updated 11 February 2013


Diclofenac is a non-steroidal anti-inflammatory medication. It is prescribed to relieve inflammation, swelling, stiffness and pain.


Diclofenac is the active ingredient of A-Lennon Diclofenac, Adco-Diclofenac, Arthru-Derm, Austell-Diclofenac, Be-Tabs Diclofenac, Cataflam D, Dicloflam, DicloHexal, Fortfen SR, Infla-Ban, Merck-Diclofenac, Panamor, Sandoz Diclofenac, Veltex, Voltaren, Voltaren Optha, Adco-Clofelam, Diclohexal-K, Dynak 50, K-Fenak and Voltaren Acti-Go.

Diclofenac is also one of multiple active ingredients found in Arthrotec (Diclofenac + Misoprostol).

General Information

Diclofenac is a non-steroidal anti-inflammatory medication. It is prescribed to relieve inflammation, swelling, stiffness and pain. It is of particular use in arthritic conditions, muscle injury, acute gout attacks and for broad spectrum pain relief. It is also often used treat migraine and painful menstrual conditions.

Diclofenac may irritate or even damage your stomach. To reduce this, it is advised to take this medication with food. This may however slow down the onset of action. For acute pain it is often recommended to take the first dose of this medication on an empty stomach. In patients with a risk of stomach irritation diclofenac is often prescribed in combination with the prostaglandin Misoprostol to protect the stomach.

How does diclofenac work?

Diclofenac blocks the production of the chemical in the body that is responsible for pain, swelling and inflammation.

Fast facts

Drug schedule: Schedule 3

Available as: Diclofenac is available as tablets, injections, suppositories, lotion, dispersible tablets, capsules and eye drops.

What does it do? Diclofenac reduces pain and inflammation.

Overdose risk: Low

Dependence risk: Low

Is diclofenac available as a generic? Yes

Is diclofenac available on prescription only? Yes

User information

Onset of effect: Within 1 hour for pain relief

Duration of action: 12 - 24 hours, depending on dosage form used

Dietary advice: Diclofenac should be taken with food to prevent gastrointestinal irritation.

Stopping this medicine: This medication can be safely stopped if used for short-term treatment. If your doctor prescribed it for longer periods of time, you should consult him/her before discontinuation.

Prolonged use: Prolonged use is more likely to cause side effects.

Special precautions

Consult your doctor before using this drug if:

  • You have asthma
  • You have a stomach ulcer
  • You have a bleeding disorder
  • You are taking blood thinning medication
  • You have porphyria
  • You are allergic to aspirin or any other medication
  • You are taking any other medication.

Pregnancy: Avoid. Potential risk to the foetus has been reported. Consult your doctor before use, or if you are planning to fall pregnant.

Breastfeeding: Avoid. This medication is passed through breast milk and may affect your baby adversely. Consult your doctor before use.

Porphyria: Porphyria

Infants and children: Caution is advised. Use only as prescribed by your paediatrician.

Elderly: Caution is advised in the elderly, as side effects are more likely

Driving and hazardous work: Caution is advised, as use of this medication may lead to dizziness, light-headedness and/or sedation. Avoid such activities until you know how this medication affects you.

Alcohol: Avoid concomitant use of alcohol with this medication, as it may worsen stomach irritation.

Possible side effects:

Side effect


Consult your doctor



Only if severe

In all cases

Gastrointestinal disorders














Swelling (feet/ankles)






Difficulty breathing



Blood in vomit


Dark, tarry stools



Drug interactions:

Blood pressure medication

Reduced pressure-lowering effect


Potential gastrointestinal symptoms


Risk of bleeding

Asthma medication

Reduced effect of asthma medication; risk of asthma attack

Cardiac glycosides, digoxin

Risk that heart failure may be more severe


Potential gastrointestinal symptoms


Potential diclofenac toxicity


Potential methotrexate toxicity


Potential risk of kidney damage

Blood glucose lowering drugs

Risk of prolonged low blood sugar


Potential baclofen toxicity

Other NSAID's

Potential risk of gastrointestinal bleeding


Risk of diclofenac toxicity

Quionolone antibiotics

Risk of seizures


Increased risk of kidney damage


Increased risk of zidovudine toxicity

Disease interactions

Consult your doctor before using this drug if you have asthma, a stomach ulcer or a bleeding disorder. The same applies if you are taking blood thinning medication, suffering from Porphyria, or if you are allergic to aspirin or any other medication.

Overdose action

A small overdose is no cause for concern. In case of intentional large overdose, seek emergency medical attention.

Recommended dosage

Adults, oral: Not to exceed 50 mg 3 times a day

Children >2 years, oral or rectal not exceeding 1-3 mg/kg in 2-3 divided doses


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