Anti-Inflammatory Agents

Anti-inflammatory agents are compounds that reduce the pain and swelling associated with inflammation. Inflammation is a response of the body to injuries such as a blow or a burn. The swelling of the affected region of the body occurs because fluid is directed to that region. The inflammatory response can aid the healing process.

In conditions such as rheumatoid arthritis, however, the swelling and increased tenderness that are characteristic of inflammation are undesirable. The intake of anti-inflammatory agents can ease the discomfort of arthritis, and other conditions such as asthma.

The relief provided by anti-inflammatory agents has been known for millennia. Hippocrates, the "father" of medicine who lived 2,500 years ago, knew infusions of willow bark could aid in relieving pain. Only a little more than 100 years ago was the basis of this relief identified as a family of anti-inflammatory chemicals called salicylates. A modified version of salicylic acid is aspirin. Today, anti-inflammatory agents are extremely popular as pain relievers. For example, over 80 billion tablets of aspirin are taken each year around the world.

There are two groups of anti-inflammatory agents, the corticosteroids and the nonsteroidal anti-inflammatory drugs (NSAIDs).

Corticosteroids are produced by the adrenal gland in carefully controlled amounts. Higher levels of the compounds are achieved by ingesting a pill or receiving an injection (the systematic route), or by use of a skin cream, nasal spray, or inhaler (the local route). Examples of corticosteroids include prednisone, prednislone, and hydrocortisone. These compounds are potent anti-inflammatory agents.

As their name implies, NSAIDs, are not steroids. In other words, they are not produced in the adrenal gland. They can be found naturally or are chemically made. Examples of NSAIDs include ibuprofen and acetylsalicylic acid (popularly known as aspirin).

Corticosteroids and NSAIDs inhibit inflammation in the same manner. Both classes of agents inhibit the production of a compound in the body called prostaglandin. Prostaglandin is made from another molecule called arachidonic acid in a reaction that depends on the activity of an enzyme called cyclooxidase. Anti-inflammatory agents prevent cyclooxidase from working properly. The shut-down of prostaglandin production curtails the inflammatory response and, because prostaglandin also aids in the passage of nerve impulses, pain is lessened.

The relief produced by anti-inflammatory agents comes with a caution, however. Side effects sometimes occur, particularly with the steroids. Corticosteroids taken over an extended period of time via the systematic route can produce fluid retention, weight gain, increased blood pressure, sleep disturbance, headaches, glaucoma, and can retard growth of children. The side effects of most NSAIDs are not so pronounced (ringing in ears, nausea, rash), and usually result from an overdose of the compound. Nonetheless, a potentially fatal condition in children called Reye syndrome has been linked to the use of aspirin, particularly if a child has recently had a bout of viral illness.