Originally, Aspirin - note the capital A - was a trademarked name of a specific preparation of acetylsalicylic acid marketed by Bayer. It has come to be the generic term for the compound, and is no longer capitalized.
Aspirin is an analgesic, or pain reducer, an anti-inflammatory and a fever reducer. As such, it is often resorted to for mild to moderate pain, such as attends chronic arthritis, colds and flu, or sports injuries. Developed in the latter part of the nineteenth century, aspirin is now known to reduce the coagulation of the blood, and in continuous low doses can provide some protection from heart attacks.
Salicylic acid, a precursor to modern aspirin, is found in a number of herbs, notably in the bark of the white willow. Use of willow bark for pain dates back at least as far as Hippocrates, and was administered by chewing the bark to extract the effective ingredient. This ingredient was extracted and combined with a buffering agent to form acetylsalicylic acid, notable for being the first constructed, or artificially produced drug ever made.
As with the drugs that followed it, aspirin was hailed as a cure-all wonder drug, and indeed, its effects are beneficial. Side effects are not unknown, however, particularly with continuous use or at higher doses.
In recent years, taking the medication has been suspected of encouraging Reyes Syndrome, a dangerous disease that can affect the brain and liver, in children and teenagers. The connection is not confirmed, yet it is recommended that people under the age of twenty use alternative pain- and fever-reducers.
Because aspirin slows the rate at which blood coagulates, people with clotting disorders such as hemophilia cannot take it. It is also discouraged for pain relief from a tooth extraction, since aspirin may cause the extraction site to continue to bleed.
Stomach problems may be complicated by the use of aspirin, and some people are allergic to it. If taken in large doses over time, as with the chronic pain of arthritis, aspirin can cause hearing problems such as ringing in the ears and loss of hearing function. If hearing problems occur, switch to a non-aspirin anti-inflammatory and hearing function generally returns to normal.