Some of the most common and widely-used over-the-counter medications are nonsteroidal anti-inflammatory drugs (NSAIDs), so it's easy to assume that they're completely safe for everyone to take. That's not always the case, however.

In fact, the Food and Drug Administration (FDA) has strengthened an existing warning on over-the-counter NSAIDs, noting that, in some cases, these medications can cause very serious or even fatal side effects.

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If you're one of the many people who takes NSAIDs even occasionally, here are five things you need to know about these over-the-counter drugs:

What are NSAIDs and how do they work?

NSAIDs are pain relievers that help reduce pain and inflammation by blocking the production of chemicals associated with these symptoms. They're used for a wide variety of ailments, including muscle pain, arthritis, toothaches, menstrual cramps and more. These medications are readily available over-the-counter in a wide variety of name brands as well as generics, and higher doses can be prescribed by a doctor.

The following are some common over-the-counter NSAIDs:

  • Aspirin (Bayer, Bufferin)
  • Ibuprofen (Advil, Motrin IB)
  • Naproxen (Aleve)

What risks are involved?

Any drug can cause side effects or an allergic reaction, but NSAIDs have been associated with an increased chance of having a heart attack or stroke. The risk may rise the longer you use NSAIDs, though it's still a possibility even if you've only used the drug for a short period of time.

Although aspirin is an NSAID, it isn't included in this revised warning. Aspirin helps protect against heart attacks, since it prevents platelets from clumping together and forming dangerous clots. Non-aspirin NSAIDs can affect an enzyme that promotes clotting, so they can raise your risk of having a heart attack or stroke.

In addition, people who take NSAIDs are more likely to have ulcers and kidney issues.

Should you keep taking NSAIDs?

That's a conversation you should have with your doctor. You should talk with him or her about your use of the medication, how it affects your pain and inflammation and whether an alternative medication may provide the same benefits but be safer for you to take.

NSAIDs may be safest for young people without a history of cardiovascular disease who use them only occasionally, said Peter Wilson, an Emory University professor of medicine and health. He recommends that people who are over age 65 and have a history of heart disease be particularly cautious.

The FDA also recommended taking your risk factors for heart disease into account. If you smoke, have high blood pressure, high cholesterol or diabetes, your risk can be higher. If you have a history of ulcers or kidney disease, you should also talk to your doctor about alternatives to NSAIDs.

What should you do if you continue to take NSAIDs?

If you smoke, work on quitting, and take care of your other risk factors while seeing your doctor regularly, according to the FDA.

In addition, take the smallest effective dose, since higher doses are linked to an increased risk of side effects. Low to moderate doses are often successful at treating swelling and pain. And when your pain has been reduced to a dull ache, try to stop taking NSAIDs and switch to another way relieve your pain.

Be sure to read labels of other medications to make sure that they don't also contain an NSAID, or you could be inadvertently double-dosing. For example, cold medications that treat multiple symptoms often include an NSAID.

What are some alternatives to try?

You can talk to your doctor about other medications, but you should also discuss any side effects they may have.

Harvard Medical School recommends the following non-medicinal alternatives:

  • Acupuncture
  • Biofeedback
  • Heat from a hot shower, bath or heating pad
  • Ice
  • Yoga or stretching
  • Physical therapy