Sooner or later, any athlete will need a non-prescription pain reliever for a minor injury such as muscle strain or tendinitis. There was a time when the choice was simple because the only non-prescription pain reliever available was aspirin.

But over the years, several new pain relievers with long, unpronounceable names have been developed and it can be confusing to know which one to take for what.

Below is a guide to over-the-counter pain relievers. All reduce fever as well as muscular pain. All but one are anti-inflammatories, which means they help reduce swelling. And all come with warnings that should be taken seriously:

• Do not take these medications if you have liver disease, asthma, kidney disease, or ulcers.

• If you take prescription medications or other non-prescription medications, check with your doctor or pharmacist before taking an over-the-counter pain reliever; there can be adverse interactions and side effects.

• Do not mix alcohol with these pain relievers.

• If you develop side effects such as gastritis (irritation of the stomach) or abdominal pain, discontinue the medication and discuss further with your physician. It is important to keep your physician informed of all medications you are taking.

• It is best to limit non-prescription pain relievers to occasional use for up to one or two weeks maximum. If longer-term use is required, see your physician for advice.

These are the most common non-prescription pain relievers that can be used for minor aches, pains, and injuries:

Aspirin (many brands)

• Reduces pain and inflammation

• Can be taken three to four times per day

• May cause stomach upset; buffered forms are available

• Do not use during final three months of pregnancy

Ibuprofen (Advil, Motrin, Nuprin, and others)

• Reduces pain and inflammation

• Can be taken three to four times per day

• May cause mild heartburn, upset stomach, or stomach pain

• Do not use during final three months of pregnancy

Naproxen (Aleve and others)

• Reduces pain and inflammation

• Can be taken up to twice per day

• Should be taken with food to avoid stomach upset

• Do not use during final three months of pregnancy

Ketoprofen (Orudis)

• Reduces pain and inflammation

• Can be taken three or four times per day

• Not to be used by children under 16 unless directed by a physician

Acetaminophen (Tylenol, Panadol, and others)

• Reduces pain, but not inflammation

• Can be taken three to four times per day

• Unlikely to cause stomach irritation

The information, including opinions and recommendations, contained in the Web site is for general educational purposes only. Such information is not intended to be a substitute for professional medical advice, diagnosis, or treatment. No one should act upon any information on this Web site without first seeking medical advice from a qualified medical physician with whom they have a confidential doctor/patient relationship.