Nonsteroidal Anti-inflammatory Drugs (NSAIDs)

Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) are used primarily to treat inflammation, mild to moderate pain, and fever.

How It Works

Nonsteroidal anti-inflammatory drugs (NSAIDs) block the activity of enzymes in the cell called cyclooxygenases (COX). There actually are two Cox enzymes, Cox-1 and Cox-2, both of which are responsible for the production of prostaglandins, chemicals in the body which promote inflammation, pain, and fever. NSAIDs block the Cox enzymes and reduce prostaglandins throughout the body. As a consequence, ongoing inflammation, pain, and fever are reduced.

Complications

Cox-1 produces prostaglandins that support platelets and protect the stomach. Since the prostaglandins that protect the stomach and support the platelets and blood clotting also are reduced, NSAIDs can cause ulcers in the stomach and promote bleeding. NSAIDs differ in how strongly they inhibit Cox-1 and, therefore, in their tendency to cause ulcers and promote bleeding.

One NSAID, celecoxib (Celebrex), blocks Cox-2, but has little effect on Cox-1. This drug is referred to as one of the selective Cox-2 inhibitors and causes less bleeding and fewer ulcers than other NSAIDs.

Uses

Specific uses for NSAIDs include the treatment of:

• Headaches
• Arthritis
• Sports injuries
• Menstrual cramps.

Aspirin (a common NSAID) is used to inhibit the clotting of blood and prevent strokes and heart attacks in individuals at high risk.

Aspirin is a unique NSAID, not only because of its many uses, but because it is the only NSAID that is able to inhibit the clotting of blood for a prolonged period (4 to 7 days). This prolonged effect of aspirin makes it an ideal drug for preventing the blood clots that cause heart attacks and strokes. Most other NSAIDs inhibit the clotting of blood for only a few hours.

The action of aspirin as antitrombothic agent depends upon the dose administered. Aspirin is a potent antithrombotic agent at low dose, but when it is used at high doses the selectivity of action upon COX1/COX2 reduces and the antithrombotic action is tapered to a very low grade.

Other matters of interest are the complex relationships between low dose aspirin, prescribed to prevent thrombotic events in patients with high risk to develop ischemic events in the heart or in the brain and the co-administration of NSAIDs.

The co-administration of low dose Aspirin and of a non steroidal anti-inflammatory agent may increase the gastroenteric toxicity of both drugs and, in turn, may also reduce the antitrombotic effect of aspirin. Controversial data are available about the co-administration of low dose aspirin and Cox-2 selective agents both as it regards the gastroenteric toxicity and antithrombotic effect.

Ketorolac (Toradol) is a very potent NSAID and is used for moderately severe pain that usually requires narcotics. Ketorolac causes ulcers more frequently than any other NSAID and is, therefore, not used for more than five days.

Although NSAIDs have a similar mechanism of action, individuals who do not respond to one NSAID may respond to another.

NSAIDs also are included in many cold and allergy preparations.

Side Effects

• The most common side effects are nausea, vomiting, diarrhea, constipation, decreased appetite, rash, dizziness, headache, and drowsiness.

• NSAIDs may also cause fluid retention, leading to swelling of feet, legs, and hands.

• The most serious side effects are kidney failure, liver failure, ulcers and prolonged bleeding after an injury or surgery.

• Some individuals are allergic to NSAIDs and may develop shortness of breath when an NSAID is administered. People with asthma are at a higher risk for experiencing serious allergic reaction to NSAIDs. Individuals with a serious allergy to one NSAID are likely to experience a similar reaction to a different NSAID.

• Use of aspirin in children and teenagers with chicken pox or influenza has been associated with the development of Reye's syndrome. Therefore, aspirin and nonaspirin salicylates should not be used in children and teenagers with suspected or confirmed chicken pox or influenza.

Interactions

• NSAIDs reduce blood flow to the kidneys and therefore reduce the action of diuretics and decrease the elimination of lithium (Eskalith) and methotrexate (Rheumatrex).

• NSAIDs also decrease the ability of the blood to clot and therefore increase bleeding time. When used with other drugs that also increase bleeding time, there is an increased likelihood of bleeding complications. Therefore, individuals who are taking drugs that reduce the ability of blood to clot should avoid prolonged use of NSAIDs.

• NSAIDs may also increase blood pressure in patients with high blood pressure and therefore counteract the action of drugs that are used to treat this problem.

Other Names

The following list contains NSAIDs that are commonly used:

• Aspirin
• Salsalate (Amigesic)
• Diflunisal (Dolobid)
• Ibuprofen (Motrin)
• Ketoprofen (Orudis)
• Nabumetone (Relafen)
• Piroxicam (Feldene)
• Naproxen (Aleve, Naprosyn)
• Diclofenac (Voltaren)
• Indomethacin (Indocin)
• Sulindac (Clinoril)
• Tolmetin (Tolectin)
• Etodolac (Lodine)
• Ketorolac (Toradol)
• Oxaprozin (Daypro)
• Celecoxib (Celebrex)