NSAIDs are most effective for mild to moderate pain accompanied by swelling and inflammation. These drugs relieve pain by inhibiting an enzyme in your body called cyclooxygenase. This enzyme makes hormone-like substances called prostaglandins, which are involved in the development of pain and inflammation. NSAIDs are especially helpful for arthritis and pain resulting from muscle sprains, strains, back and neck injuries or cramps.

When taken as directed, NSAIDs are generally safe. But if more than the recommended dosage is taken — and sometimes even the recommended dosage — NSAIDs may cause nausea, stomach pain, stomach bleeding or ulcers. Large doses of NSAIDs can lead to kidney problems and fluid retention. Risk increases with age. If you regularly take NSAIDs, talk to your doctor so that he or she can monitor you for side effects.

NSAIDs have a so-called ceiling effect, or limit to how much pain they can control. This means that beyond a certain dosage, they don't provide additional benefit. If someone has moderate to severe pain, exceeding the dosage limit may not help relieve the pain.

Many NSAIDs require a prescription, but some lower-dose NSAIDs, such as aspirin and ibuprofen, are available over-the-counter.

Flurbiprofen (Ansaid)

Flurbiprofen is a member of the phenylalkanoic acid derivative family of non-steroidal anti-inflammatory drugs (NSAIDs). It is also known by the trade name ANSAID and marketed by Pfizer. Flurbiprofen is used for the treatment of inflammation and pain caused by rheumatoid arthritis and osteoarthritis, as well as soft tissue injuries, such as tendinitis and bursitis.  This drug should be taken with food.

Flurbiprofen is also used as an active ingredient in some kinds of throat lozenges. R--flurbiprofen is the single enantiomer of racemate flurbiprofen; this compound is currently in clinical trials for the treatment of metastatic prostate cancer, and Alzheimer's disease.

Flurbiprofen may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• headache

• nervousness or anxiety

• depression

• memory problems

• shaking of a part of the body that you cannot control

• difficulty falling asleep or staying asleep

• vomiting

• gas

• constipation

• diarrhea

• runny nose

• ringing in the ears