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Highlights for diclofenac
Oral tablet

Diclofenac is an anti-inflammatory drug. It comes in other forms, including eye drops, powder packets, and transdermal gel, patch, and solution.


Talk to your doctor before taking diclofenac if you have heart disease or high blood pressure. It could make your condition worse.


Common side effects include stomach pain, nausea, and others.

FDA warning Details
increased blood pressure
May cause increased blood pressure, puffiness, or water retention
liver function
May affect some of your liver function tests See Details
allergic reaction
May cause allergic reaction See Details
Drug Features

Diclofenac is a prescription drug. It is available in these forms: oral (capsules, tablets), eye drops, transdermal gel, transdermal patch, transdermal solution, and powder packets for oral solution.

Diclofenac is available in its generic form. Generic drugs usually cost less. In some cases they may not be available in every strength or form as the brand. Talk to your healthcare provider to see if the generic will work for you.

Why It's Used

Oral diclofenac is used to treat:

  • arthritis and rheumatoid arthritis
  • mild to moderate pain
  • painful menstrual cramps
How It Works

Diclofenac is a nonsteroidal anti-inflammatory drug (NSAID).

The drug works by blocking a particular enzyme in your body. When the enzyme is blocked, your body decreases the amount of inflammatory chemicals it makes. This helps to reduce inflammation and pain.

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Content developed in collaboration with Susan J. Bliss, RPh, MBA

Medically reviewed by Stacey Boudreaux, PharmD and Alan Carter, PharmD on February 3, 2015

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Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up-to-date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or other healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.

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FDA Warning

Diclofenac has a Black Box Warning. This is the most serious warning from the Food & Drug Administration (FDA). Though the medication can still be sold and used, a black box warning alerts doctors and patients to potentially dangerous effects.

Warning: Diclofenac is a nonsteroidal anti-inflammatory drug (NSAID). All NSAIDs can increase your risk of heart attack or stroke. This risk can go up the longer you use NSAIDs. Talk to your doctor before taking diclofenac if you have heart disease.

You shouldn't take diclofenac before you have surgery, especially heart bypass surgery. Talk to your doctor if you take diclofenac and will have surgery soon.

NSAIDs like diclofenac can increase your risk of serious side effects, including stomach bleeding or ulcers. 

May affect some of your liver function tests

Your doctor should monitor liver function while you take diclofenac.

May cause allergic reaction

If you have an allergy to aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs), talk to your doctor before taking diclofenac.

How It Works

Metoprolol belongs to a class of drugs called beta blockers. A class of drugs refers to medications that work similarly in your body. They have a similar chemical structure and are often used to treat similar conditions.

Beta blockers prevent norepinephrine (adrenalin) from acting on beta receptors in blood vessels and in the heart. This causes blood vessels to relax. By relaxing the vessels, beta blockers help to lower blood pressure and reduce chest pain. Blood pressure is often raised because vessels are tightened. That puts a strain on the heart and increases the body's oxygen demand. Beta blockers help to lower the heart rate and the heart's demand for oxygen.

Beta blockers don't permanently change blood pressure and chest pain. Instead, they help to manage the symptoms.

People with high blood pressure or water retention

If you have high blood pressure or water retention, tell your doctor before taking diclofenac. Your heart may already be working hard and adding an NSAID can increase this workload.

People with ulcer or digestive bleeding

If you've had an ulcer or bleeding from your digestive system, ask your doctor before taking diclofenac. You're at increased risk for another bleed.

People with a history of smoking, alcohol use

Smokers and those who drink alcohol regularly have an increased risk of ulcer from NSAIDs like diclofenac.

People with kidney disease, diuretics

If you have kidney disease or take diuretics (water pills), there's a risk this drug can affect your kidneys' ability to remove excess water from your body. Ask your doctor is diclofenac is the right drug for you.

People with asthma with aspirin reaction

If you have asthma and you react to aspirin, you could have a bad reaction to diclofenac. Talk to your doctor before taking the drug.

Pregnant women

Pregnancy category C/Pregnancy category D after 30 weeks of pregnancy

Diclofenac is a category D pregnancy drug after 30 weeks of pregnancy. Category D means two things:

  1. Studies show a risk of adverse effects to the fetus when the mother takes the drug.
  2. The benefits of taking atenolol during pregnancy may outweigh the potential risks in certain cases.

With diclofenac, babies of women who have reached 30 weeks of pregnancy have had side effects from the drug, and there is an increased risk of miscarriage. Do not take diclofenac if you're pregnant, unless your doctor advises you to.

Until the 30th week, diclofenac is a category C drug. That means that studies have shown that diclofenac can be a risk to the offspring of lab animals. However, not enough studies have been done to show risk in humans.

Women who are nursing

This drug passes into the breast milk, which means it can pass to a nursing child. This may lead to toxic effects for the child.

Breastfeeding isn't recommended if you're taking diclofenac.

For Seniors

Seniors are at higher risk for stomach problems, bleeding, water retention, and other side effects from diclofenac.

Seniors may also have kidneys that aren't working at peak levels, so the drug can build up and cause more side effects.

When to call the doctor

If your pain doesn't improve, or if the swelling, redness, and stiffness of your joint(s) don't improve, call your doctor. The drug may not be working for you.


If you have an allergy to aspirin or other similar non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or naproxen, you could have an allergic reaction to diclofenac. Call your doctor right away if you have any signs of:

  • wheezing
  • trouble breathing
  • hives
  • itchy rash
Always take diclofenac with food

Eat something that coats your stomach, such as a meal or at least a glass of milk. Start eating, take your diclofenac, and then finish your meal.

Don't crush or cut diclofenac tablets

Many of them are timed-release, while others have a film coating and can't be cut.

If you can't swallow the tablets or have stomach side effects, your doctor may give you a topical version or a different treatment.

Store the tablets at room temperature: 68–77°F (20–25°C)

Store the immediate release, extended release, and delayed release tablets at room temperature: 68–77°F (20–25°C).

Delayed release tablets can absorb moisture, so keep them in a tightly closed bottle.

Note: Be careful of moist environments, including bathrooms. To keep drugs away from moisture, store them somewhere other than your bathroom and any other damp location.

Clinical Monitoring

If you take diclofenac for a long time, your doctor should do blood tests to check your kidney and liver function at least once a year.

You should check your own blood pressure occasionally.

Sun Sensitivity

You may have increased sensitivity to the sun while taking diclofenac.

Use a SPF 30 or greater sunscreen to protect your skin.