What is diclofenac, and how does it work (mechanism of action)?

Diclofenac belongs to a class of drugs called nonsteroidal anti-inflammatory drugs (NSAIDs) that are used for the treatment of mild to moderate pain, fever, and inflammation. Other members of this class include ibuprofen (Motrin), indomethacin (Indocin), nabumetone (Relafen), naproxen (Aleve) and several others. NSAIDs work by reducing the production of prostaglandins, chemicals that cause pain, fever and inflammation. NSAIDs block the enzyme that makes prostaglandins (cyclooxygenase), resulting in lower production of prostaglandins. As a consequence, inflammation, pain and fever are reduced. Since the response to different NSAIDs varies from patient to patient, it is not unusual for a doctor to try different NSAIDs for any given condition. The FDA approved diclofenac in July 1998.

What brand names are available for diclofenac?

Voltaren, Cataflam, Voltaren-XR, Cambia, Zipsor, Zorvolex

Is diclofenac available as a generic drug?

GENERIC AVAILABLE: Yes

Do I need a prescription for diclofenac?

Yes

What are the side effects of diclofenac?

The most common side effects of diclofenac involve the gastrointestinal system, such as:

• ulcerations,
• abdominal burning,
• pain,
• cramping,
• nausea,
• gastritis,
• serious gastrointestinal bleeding, and
• liver toxicity.

Sometimes, stomach ulceration and bleeding can occur without any abdominal pain. Black tarry stools, weakness, and dizziness upon standing may be the only signs of internal bleeding. Rash, kidney impairment, ringing in the ears, and lightheadedness are also seen.

Other important side effects include:

• Fluid retention,
• blood clots,
• heart attacks,
• hypertension, and
• heart failure.

People who are allergic to other NSAIDs should not use diclofenac. NSAIDs reduce the flow of blood to the kidneys and impair function of the kidneys. The impairment is most likely to occur in patients with already reduced kidney function or congestive heart failure, and use of NSAIDs in these patients should be done cautiously. Individuals with asthma are more likely to experience allergic reactions to diclofenac and other NSAIDs.

What is the dosage for diclofenac?

Diclofenac should be taken with food to reduce stomach upset. The recommended dose for most conditions is 100-200 mg daily. Dosing intervals are 2 to 4 times daily depending on the diclofenac formulation used and the condition being treated.

Is diclofenac safe to take if I'm pregnant or breastfeeding?

It is not known whether diclofenac is excreted in breast milk.

What else should I know about diclofenac?

What preparations of diclofenac are available?

Tablets (delayed release): 25, 50 and 75 mg. Tablets (immediate release): 50 mg. Tablets (extended release): 100 mg. Capsule: 25 mg. Oral Solution: 50 mg

How should I keep diclofenac stored?

Diclofenac should not be stored above 30 C (86 F) and should be protected from moisture.