If you’re looking for relief from the symptoms of a cold, fever, or the flu, you’ll find many over-the-counter (OTC) options at your local pharmacy.

The pain and fever-reducing ingredients often found in these medicines -- acetaminophen, aspirin, ibuprofen, and naproxen sodium -- are safe for most adults if taken correctly. But in the throes of fever or the flu, you may not think as clearly about safety.

To be prepared, read this primer on OTC pain relievers, so that when illness strikes, you’ll know how they work to reduce fever, aches, and pains and how to use them safely.

Two common groups of pain relievers are acetaminophen and nonsteroidal anti-inflammatory drugs (NSAIDs). Most OTC pain relief drugs contain one or the other.

These medications don’t make illnesses go away, but they can relieve some symptoms so you suffer less while the cold, flu, or fever works its way through your system.

NSAIDs. This group of drugs relieves pain and fever by tamping down on the substances in your body that cause the feeling of pain, and they help control body temperature.

Drugs in the NSAID category include:

Aspirin, found in Bayer or St. Joseph

Ibuprofen, the active ingredient in Advil and Motrin

Naproxen sodium, found in Aleve

Acetaminophen. This is an active ingredient in Tylenol and many other prescription and non-prescription medications. Acetaminophen seems to work on the parts of the brain that perceive pain and control body temperature.

NSAIDs are safe for most people when taken at the right dose for a short period. However, they can increase risk of serious stomach bleeding. NSAIDs may also increase the chance of heart attack and stroke.

Ask a doctor before using NSAIDs if:

Combining NSAIDs with more than two to three alcoholic drinks a day for women or three to four for men increases the risk of stomach bleeding. Taking NSAIDs along with blood-thinning medications can also increase the risk of bleeding, including serious stomach bleeding. Talk to your doctor if you drink alcohol or take blood-thinning medicines before using an NSAID. Other factors that increase the risk of stomach bleeding include:

Having a previous history of stomach bleeding

Being over age 60

Taking steroid medications, or other NSAID medications

Risks of Using Acetaminophen for Pain Relief

The most serious risk from acetaminophen is liver damage. Ignoring the dose recommended on the label can put you at risk of severe liver damage.

People who are at greater risk for liver damage from acetaminophen include people with liver disease and men who drink three or more alcoholic drinks a day (or two a day or more drinks for women).

Talk to your doctor or pharmacist if you also take the blood thinner warfarin (Coumadin), because it may increase the risk of bleeding.

It is important to read the package labeling carefully and not exceed the maximum daily dosage. Because many other OTC and prescription products contain acetaminophen as an active ingredient, make sure to look at the list of active ingredients in other medicines you are taking in order to avoid overdosing.

Because the signs and symptoms of liver damage from acetaminophen may not be immediately noticeable, if you think you may have taken too much, call 911 or poison control (800-222-1222) immediately.

OTC pain relievers are often used with other ingredients in prescription and non-prescription medications, including some for arthritis, menstrual symptoms, allergies, and sleeplessness. To avoid an overdose, it’s important not to take two medicines that contain the same pain reliever.

Mixing medicines that contain different pain relievers can also cause problems and should not be done without talking to a doctor.

Because of the risks of overdosing on pain medication, it’s important to keep track of how much you take and how long you take it.

Follow these other drug safety tips for using OTC pain relievers:

Safe Pain Relief for Children

Drugs work differently in children than they do in adults. Take extra care when giving your child acetaminophen or ibuprofen and only use those products labeled specifically for your child’s age group. Adult medicines and doses are too strong for most kids and should not be given to children.

Beyond not giving aspirin to children and teens (ages 18 and under) due to the risk of Reye's syndrome, follow these safety measures:

For some people, acetaminophen is the best way to reduce certain cold and flu symptoms. For others, ibuprofen does the trick. For many, both are equally effective.

How do you know which to take? Talk to your doctor or pharmacist about the other medicines you are taking and your medical history, such as problems with your heart, kidneys, stomach, or liver, or if you take anti-clotting medication or medication for high blood pressure.