Acetylsalicylic is the chemical name for the common pain reliever aspirin. It is a nonsteroidal anti-inflammatory drug that works to relieve pain by reducing the amount of chemicals in the body that cause pain, inflammation and fever, according to Drugs.com. A low-dose aspirin regimen is also used by some people to prevent heart attacks. For most people, acetylsalicylic acid is well-tolerated. Most reported side effects are related to the aspirin dosage, with large doses or long-term use associated with more side effects. Because of this, it's best to take the lowest effective dose to meet your needs.
Stomach Ulcers
When taken regularly, acetylsalicylic acid can cause stomach ulcers in some people, according to the American College of Gastroenterology. Some people experience abdominal pain when ulcers develop, but for some the ulcers form with no pain. In some cases, people who develop stomach ulcers may also experience bleeding in the stomach. Signs of internal bleeding include black or tarry stools, dizziness and weakness. People who use a low-dose aspirin regimen are not as likely to experience these effects as those who use it to control pain and inflammation.
Upset Stomach
An upset stomach or abdominal discomfort can also develop in people who use aspirin, according to Drugs.com. Some users also experience nausea and vomiting as a side effect.
Liver Damage
Taking high doses of aspirin over a long time period can be toxic to the liver, resulting in damage to the organ, according to Drugs.com. Serious liver conditions such as cholestatic hepatitis can also develop.
Tinnitis
Tinnitis, or ringing in the ears, can be another side effect of acetylsalicylic acid. However, when this develops, the dosage can be lowered to a level that does not induce this effect.
Reye's Syndrome
A serious and potentially life-threatening condition called Reye's syndrome has been reported in some cases of children with a fever being given aspirin. The condition begins with vomiting but also causes liver damage and neurological impairment. Because of this risk, children with a fever should never be given aspirin-containing products. Suitable alternatives include ibuprofen and acetaminophen.
Heartburn
Some people who use acetylsalicylic acid have reported heartburn as a side effect, according to Drugs.com.
Headaches
Aspirin use has been linked to headaches in some people. When taken in excess, aspirin can cause what is known as an analgesic rebound effect, which happens when your body is used to taking aspirin to relieve headache pain and comes to expect each dose---a type of chemical dependency.
