For more than 100 years, aspirin has been among the most popular medications for treating mild to moderate pain. Introduced into the United States in 1899, it also reduces inflammation, fever, redness, swelling and discomfort caused by medical disorders such as headaches, infections and arthritis. It also helps reduce clotting of blood. Aspirin belongs to a class of medications known as nonsteroidal anti–inflammatory drugs (NSAIDs).
Aspirin is derived from salicylate, a naturally occurring substance found in the bark of willow trees that has been used for hundreds of years to relieve pain. Scientists are unsure exactly how the substance works, but do know that it prevents pain by acting on the hypothalamus (part of the brain that regulates body temperature and other autonomic activities) and blocking the generation of pain impulses. It also reduces inflammation by inhibiting prostaglandin production. Prostaglandins are hormone–like substances in the body that mediate a wide range of physiological functions.
Aspirin comes in many formulations and dosage levels. Although the drug is largely safe and effective, it can produce dangerous side effects for people with certain health conditions or for special populations, especially children. People are advised to talk with a physician before using aspirin.
For more than 100 years, aspirin has been used to treat numerous ailments, including mild to moderate pain. This drug reduces inflammation, fever, redness, swelling and discomfort caused by medical disorders such as headaches, infections and arthritis. Aspirin also helps prevent blood from clotting, and has been shown to reduce the risk of heart attacks and strokes.
Aspirin is another name for acetylsalicylic acid. Salicylate is a naturally occurring substance found in the bark of willow trees that was used for hundreds of years as a way to relieve pain. Aspirin was introduced to the U.S. market in 1899. It belongs to a class of medications known as nonsteroidal anti–inflammatory drugs (NSAIDs).
Scientists are not exactly sure how aspirin works. However, they know it prevents pain by acting on the hypothalamus (part of the brain that regulates body temperature, metabolic processes and other autonomic activities) and blocking the generation of pain impulses. It also reduces inflammation by inhibiting prostaglandin production. Prostaglandins are hormone–like substances in the body that help regulate a wide range of physiological functions.
Today, aspirin remains one of the most popular drugs worldwide for treating cases of mild to moderate pain. It is available in tablets (regular, coated, extended–release, chewable and effervescent dissolved in liquid), capsules, gums and suppositories. It is usually taken in an over–the–counter formulation but is also available in prescription strength. People sometimes assume that nonprescription drugs do not have significant risks, but side effects of aspirin can include gastric bleeding and kidney damage.
Recent research suggests that taking aspirin or other NSAIDs around the time of a vaccine might reduce the shot’s effectiveness. Patients may wish to consult their physician about whether to suspend use of aspirin when getting a vaccination. Patients should dispose of aspirin that has the odor of vinegar, as this indicates that the aspirin is likely degraded.
Types and differences of aspirin
Aspirin is available in many generic, store and brand names, both over the counter and in prescription strength. Brand names include: Adprin
ZORprin Some brands contain caffeine, antacids or other ingredients. There are also combination products that contain aspirin and another medication such as an anti-anxiety agent, anticoagulant, barbiturate or opioid.
Conditions treated with aspirin
Aspirin is used to alleviate numerous kinds of pain caused by many conditions, including:
- Headaches, including tension headache and migraine
- Arthritis, including osteoarthritis and rheumatoid arthritis
- Other sources of joint pain, ranging from whiplash to tennis elbow
- Back pain
- Muscle aches
- Dental pain
A physician may advise a patient who has or is at risk of heart disease to take daily low-dose aspirin as a preventive measure. Interested individuals are advised to ask their physician about the risks and benefits of aspirin therapy.
In addition, regular use of aspirin or other nonsteroidal anti-inflammatory drugs may reduce the risk of some forms of cancer.
Conditions of concern with aspirin
Patients should inform their physician if they are allergic to aspirin, arthritis or pain medications, or any other drugs. Other conditions of concern in patients considering using aspirin include:
- Diabetes or other endocrine disorders
- Hemophilia or other bleeding problems
- Uncontrolled high blood pressure
- Hodgkin’s disease
- Kidney disease or conditions that can damage the kidneys, such as lupus or sickle cell anemia
- Liver disease
- History of nasal polyps
- History of ulcers
Patients who are planning to have arthroplasty, spine surgery or other surgery should inform their physician if they are taking aspirin. Patients may be asked to stop taking aspirin for one week before surgery.
Potential side effects of aspirin
Some people find that taking aspirin upsets their stomach. To avoid this side effect, patients should take aspirin with meals, or a full glass of water or milk. Buffered aspirin, which is coated with an antacid, may help prevent this side effect. Symptoms associated with upset stomach from aspirin may include stomach pain and vomiting.
In some cases, patients who take aspirin experience serious gastrointestinal disorders such as ulceration of the stomach lining or bleeding of the gastrointestinal tract or urinary tract. High doses of aspirin have been known to cause hearing loss, which is usually preceded by a ringing sound in the ears known as tinnitus.
Aspirin can also trigger blood problems such as decreased counts of white blood cells and platelets, and hemolytic anemia (inadequate number of circulating red blood cells caused by premature destruction of these cells). In addition, people who take aspirin are at risk for increased bleeding. For example, patients with cuts or nosebleeds may find that they bleed longer than they otherwise would. In most instances, this is not a serious problem. However, in some patients it can lead to increased bleeding of ulcers or, rarely, bleeding in the brain (hemorrhagic stroke).
- Sudden-onset acute kidney failure can occur in people with risk factors including old age, chronic kidney disease, systemic lupus erythematosus or alcohol abuse.
- Chronic kidney damage (analgesic nephropathy) can develop in anyone taking these drugs daily over several years. This risk increases when combining two or more analgesics (especially aspirin and acetaminophen together) with caffeine or the opioid codeine.
Some patients have an allergic reaction to aspirin. This may cause a person’s face to swell, a condition known as angioedema. In some cases, this allergy can bring on an asthma attack.
Patients who experience any of the following more substantial side effects should contact their physician immediately:
- Ringing in the ears, ear pain or loss of hearing
- Bloody or black stools
- Wheezing or other breathing difficulties
- Mental confusion
- Skin rash
Drug or other interactions with aspirin
Patients should consult their physician before taking any additional prescriptions, over–the–counter medications, nutritional supplements or herbal medications. Patients should not drink alcohol while taking aspirin. Certain medications can interact with aspirin, including:
- Diabetes medications
- Blood pressure medications, such as beta blockers and ACE inhibitors
- Gout medications
- Acetazolamide (medication often used to treat glaucoma)
- Methotrexate (a disease-modifying antirheumatic drug)
- Nizatidine (medication used to treat and prevent ulcers, as well as occasional heartburn and acid indigestion)
- Valproic acid (an anticonvulsant used to control certain types of seizures, prevent migraines and treat manic episodes of bipolar disorder)
There is evidence that caffeine helps boost the effects of aspirin, possibly by lifting a patient’s mood. Some brands combine aspirin and caffeine, and some experts suggest that patients can receive this benefit by taking two aspirin and drinking a cup of coffee. However, there is no proof that caffeine helps relieve pain.
Symptoms of aspirin overdose
Symptoms of overdose can be similar to the medication’s side effects, but are usually more severe. Patients exhibiting any of these signs or symptoms should contact their physician immediately:
- Decreased urine output and swelling of the feet, ankles and legs. This which could indicate acute renal failure.
- Gastrointestinal discomfort.
- Unusually high body temperature.
- Ringing or buzzing in the ears or ear pain.
- Rapid breathing, confusion or lethargy, which could indicate metabolic acidosis (accumulation of acids in the body) with respiratory alkalosis (alkalinity of the blood and tissues resulting from abnormal loss of carbon dioxide due to hyperventilation).
Patients should contact their physician immediately if they suspect overdose with aspirin. Patients who overdose on aspirin can usually be successfully treated with administration of ipecac syrup (medication that induces vomiting), gastric lavage (washing out the stomach with sterile water or a salt–water solution) or activated charcoal (medication that neutralizes poisons that have been swallowed).
Pregnancy use issues with aspirin
Studies have indicated that aspirin may cause birth defects in humans. As a result, it is recommended that pregnant women not use aspirin. Aspirin passes into breast milk. It should not be taken by women who are breastfeeding unless recommended by a physician.
Child use issues with aspirin
Infants and children should not take aspirin. Use of aspirin in children has been associated with Reye’s syndrome, a rare but extremely serious condition that affects all organs of the body and that can be fatal. The danger is most present in children who take aspirin when they have a viral infection, the flu or chicken pox. Symptoms include:
- Behavioral changes, including belligerence
As a result of this danger, experts often suggest that aspirin not be used by anyone under the age of 18, especially if they have a viral illness.
Elderly use issues with aspirin
Patients older than age 60 may be more susceptible to the toxic effects of aspirin. In addition, aspirin can affect renal prostaglandins (hormone–like substances in the body that mediate a wide range of physiological functions), causing fluid retention and edema (excessive watery fluid in cells, tissues or serous cavities).
This can be a significant medical problem for older people. Older people who mix aspirin use with alcohol consumption also are at high risk for episodes of gastric bleeding. As a result of these risks, older patients should use aspirin carefully and in close consultation with a physician.
Aspirin is being studied to determine its effectiveness in treating migraines. So far, studies have been mixed regarding the effectiveness of aspirin as a migraine treatment. Combining caffeine with aspirin appears to have increased benefit in treating migraines. However, aspirin appears to offer less benefit that other medications used to treat migraines.
Recent research suggests that regular use of aspirin or some other nonsteroidal anti-inflammatory drugs (NSAIDs) might help prevent conditions including some cancers, benign prostatic hyperplasia and asthma. Scientists conducting such research generally advise that people not take aspirin for such purposes because of the gastrointestinal and other side effects, but that these potential benefits may be a bonus in people taking aspirin on their physician’s advice for reasons such as relieving arthritis or preventing blood clots.
Questions for your doctor regarding aspirin
Preparing questions in advance can help patients have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctor the following questions about aspirin:
- Is it safe for me to take aspirin?
- What kinds of pain can I treat with aspirin?
- I know aspirin relieves pain, but do I have other conditions it can treat?
- Is aspirin available to me in prescription dosages to treat more substantial pain?
- What side effects might I experience from taking aspirin? Am I at risk of ulcers?
- When should I notify you of side effects?
- Do I have any conditions or use any medications that make it unwise to use aspirin?
- When should I take other pain relievers, such as acetaminophen, and how do these other drugs differ from aspirin?
- Can I take aspirin on an empty stomach?
- What are my other treatment options if aspirin does not ease my pain?
- Should I take daily aspirin to reduce my risk of heart attack, cancer, prostate enlargement, asthma or any other conditions?