Aspirin, also known as Acetylsalicylic Acid is a nonsteroidal antiinflammatory drug (NSAID) effective in treating fever, pain, and inflammation in the body. It also prevents blood clots (i.e., is antithrombotic). As a group, NSAIDs are non-narcotic relievers of mild to moderate pain of many causes, including headaches, injury, menstrual cramps, arthritis, and other musculoskeletal conditions. Other members of this class include ibuprofen, indomethacin, nabumetone and several others. They all work by reducing the levels of prostaglandins, chemicals that are released when there is inflammation and that cause pain and fever. NSAIDs block the enzyme that makes prostaglandins (cyclooxygenase), resulting in lower concentrations of prostaglandins. As a consequence, inflammation, pain, and fever are reduced. Inhibition of prostaglandins also reduces the function of platelets and the ability of blood to clot. Aspirin, inhibits the function of platelets in a manner that is different from other NSAIDs, and its antithrombotic effects last longer than other NSAIDs. This is why aspirin is used for preventing heart attacks and strokes. The FDA approved Bayer aspirin in June 1965.
Aspirin is part of a group of medications called nonsteroidal anti-inflammatory drugs (NSAIDs), but differs from them in the mechanism of action. Though it, and others in its group called the salicylates, have similar effects (antipyretic, anti-inflammatory, analgesic) to the other NSAIDs and inhibit the same enzyme cyclooxygenase, aspirin (but not the other salicylates) does so in an irreversible manner and, unlike others, affect more the COX-1 variant than the COX-2 variant of the enzyme. For example, NSAIDs' antiplatelet effects normally last in the order of hours, whereas aspirin's effects last for days (until the body replaces the suppressed platelets). Hence, when physicians tell patients to stop taking NSAIDs, they usually imply aspirin as well.
Today, aspirin is one of the most widely used medications in the world, with an estimated 40,000 tonnes of it being consumed each year. In countries where Aspirin is a registered trademark owned by Bayer, the generic term is acetylsalicylic acid (ASA).
Aspirin is used for the treatment of inflammation, fever, and pain that results from many forms of arthritis, including rheumatoid arthritis, juvenile arthritis, systemic lupus erythematosus, ankylosing spondylitis, Reiter's syndrome, and osteoarthritis, as well as for soft tissue injuries, such as tendinitis and bursitis. Aspirin also is used for rapid relief of mild to moderate pain and fever in other inflammatory conditions. Because aspirin inhibits the function of platelets for prolonged periods of time, it is used for reducing the risk of strokes and heart attacks.
Aspirin interferes with your blood's clotting action. When you bleed, your blood's clotting cells, called platelets, build up at the site of your wound. The platelets help form a plug that seals the opening in your blood vessel to stop bleeding.
But this clotting can also happen within the vessels that supply your heart and brain with blood. If your blood vessels are already narrowed from atherosclerosis — the buildup of fatty deposits in your arteries — a fatty deposit in your vessel can burst. Then, a blood clot can quickly form and block the artery. This prevents blood flow to the heart or brain and causes a heart attack or stroke. Aspirin therapy reduces the clumping action of platelets — possibly preventing heart attack and stroke.
In the early 1990s, strong research showed that aspirin could help in treating heart attacks. In fact, this heart disease “wonder drug” is now given to all patients who arrive at the hospital emergency department with a suspected heart attack, because aspirin acts to thin the blood and lessen the size of a blood clot during a heart attack.
But what about preventing a heart attack or heart disease with aspirin? The answer is: it depends. There are certain groups of people for whom taking aspirin makes sense; however, it does not make sense for everyone. In some situations, the risk of aspirin outweighs the benefits.
The American Heart Association recommends aspirin for people in the following groups:
People with a history of a previous heart attack, unstable angina, ischemic stroke, and transient ischemic attack (TIA) (also known as a mini stroke).
People with high risk for a heart attack.
Aspirin is not recommended for everyone, because there are possible risks with aspirin, including an increased risk for gastrointestinal bleeding and a slight increase in a certain type of stroke (hemorrhagic stroke) caused by bleeding in the brain.
Make sure to talk with your doctor before trying to prevent heart disease with aspirin. Your healthcare provider will weigh the possible benefits against the risks associated with aspirin. Before your healthcare provider recommends aspirin to prevent a heart attack, he or she will consider a number of factors, including your:
Age
Gender
Current heart disease risk factors
Personal history of heart disease
Other medications.
Also, regardless of whether you are taking aspirin, people should adopt the well-proven heart disease prevention approaches. These ways to prevent heart disease include:
Being more physically active
Maintaining a healthy weight
Eating a well-balanced, heart-healthy diet
Controlling blood pressure and cholesterol
Preventing or managing diabetes
Not smoking
In general, aspirin works well for dull, throbbing pain; it is ineffective for pain caused by most muscle cramps, bloating, gastric distension, and acute skin irritation. The most studied example is pain after surgery, such as tooth extraction, for which the highest allowed dose of aspirin (1 g) is equivalent to 1 g of paracetamol (acetaminophen), 60 mg of codeine, or 5 mg of oxycodone. A combination of aspirin and caffeine, in general, affords greater pain relief than aspirin alone. Effervescent aspirin alleviates pain much faster than aspirin in tablets (15–30 min vs. 45–60 min).
Nevertheless, as a postsurgery painkiller, aspirin is inferior to ibuprofen and has higher gastrointestinal toxicity. The maximum dose of aspirin (1 g) provides weaker pain relief than an intermediate dose of ibuprofen (400 mg), and this relief does not last as long. A combination of aspirin and codeine may have a slightly higher analgesic effect than aspirin alone; however, this difference is not clinically meaningful. It appears ibuprofen is at least equally, and possibly more, effective than this combination.
According to a 1998 meta-analysis of clinical trials for menstrual pain, aspirin demonstrated higher efficacy than placebo, but lower than ibuprofen or naproxen, although maximum doses of aspirin were never used in these trials. The authors concluded ibuprofen has the best risk-benefit ratio.
Aspirin did not ease pain during cycling exercise, while caffeine was very effective. Likewise, aspirin, codeine, or paracetamol was not better than placebo for muscle soreness after exercise.
Some studies have found that aspirin could lead to lower risks of certain types of cancer, including colorectal, prostate, stomach, and possibly breast. Ibuprofen and naproxen have also been linked to lower rates of colorectal and stomach cancers. The anti-inflammatory action of these three drugs is thought to play a role in this reduced risk. Other studies have suggested that aspirin and acetaminophen (a non-NSAID over-the-counter pain reliever) may lower the risk of ovarian cancer, but these findings have been disputed.
While there have been other studies showing regular use of aspirin or other non-steroidal anti-inflammatory drugs (NSAIDs) seems to reduce the risk of developing various cancers, including prostate cancer, this is one of the first to suggest that such drugs may help men with prostate cancer live longer.
The study led by Dr. K Khanh H. Nguyen, a radiation oncologist at Fox Chase Cancer Center was presented today at the 46th Annual Meeting of the American Society for Therapeutic Radiology and Oncology (ASTRO).
“Pretreatment NSAID use was associated with significant delays in distant metastases, decreased rates of second cancers and improvement in overall survival,” lead author Nguyen said in a news release. “Our data suggest a potential benefit of NSAIDs in managing prostate cancer.”
The Fox Chase study involved 1,206 men who had definitive radiation therapy for localized prostate cancer. The researchers compared long-term treatment outcomes of 232 patients who had used NSAIDs regularly before treatment with the outcomes of the 974 men with no history of regular NSAID use. Other characteristics, such as smoking, were balanced between the two groups. The follow-up period averaged more than four and a half years.
After taking into account other variables such as age, Gleason score and radiation dose, the use of anti-inflammatory drugs remained a predictor for improved overall survival.
Laboratory studies have suggested that by inhibiting the COX-1 and COX-2 enzymes, NSAIDs may enhance programmed cell death (apoptosis) and inhibit the development of blood vessels (angiogenesis) that feed a tumor. The Fox Chase researchers concluded that inhibiting these COX enzymes holds promise in prostate cancer treatment and warrants further studies.
Aspirin is a first-line drug in the treatment of migraine, bringing relief in 50–60% of the cases. When used at a high dose of 1000 mg (as compared to 275–325 mg when used as a pain killer or 81 mg as an antiplatelet therapy), no significant differences were seen as compared to triptan medication, sumatriptan (Imitrex) and other painkillers such as paracetamol (acetaminophen) or ibuprofen. The combination of aspirin, paracetamol (acetaminophen) and caffeine (as found in the OTC brand Excedrin) is even more potent. For the treatment of migraine headache, this formulation works better than any of its three components taken separately, better than ibuprofen and better than sumatriptan. As with all other medications for migraine, it is recommended to take aspirin at the first signs of the headache, and it is the way these medications were used in the comparative clinical trials.
Aspirin alleviates pain in 60–75% of patients with episodic tension headaches. It is equivalent to paracetamol (acetaminophen) in that respect, except for the higher frequency of gastrointestinal side-effects. Comparative clinical trials indicated metamizole and ibuprofen may relieve pain faster than aspirin, although the difference becomes insignificant after about two hours. The addition of caffeine in a dose of 60–130 mg to aspirin increases the analgesic effect in headache. The combination of aspirin, paracetamol (acetaminophen) and caffeine is still more effective, but at the cost of more stomach discomfort, nervousness and dizziness.
There is some evidence low-dose aspirin has benefit for reducing the occurrence of migraines in susceptible individuals.
The coronary arteries supply blood to the heart. Aspirin is recommended for one to six months after placement of stents in the coronary arteries and for years after a coronary artery bypass graft. The carotid arteries supply blood to the brain. Patients with mild carotid artery stenosis benefit from aspirin; it is recommended after a carotid endarterectomy or carotid artery stent. After vascular surgery of the lower legs using artificial grafts that are sutured to the arteries to improve blood supply, aspirin is used to keep the grafts open because it serves as type of blood thinner, reducing the likelihood of clots forming.
An update on Aspirin in the Primary Prevention of Cardiovascular Disease.
Rachel Eidelman, Patricia Herbert, Steven Weisman, & Charles Hennekens, from Arch Intern Med, vol. 163, Sept. 22, 2003.
A meta-study using 5 published trials from 1988 to present, totaling 55,580 randomized participants.
Results: Among the 55,580 randomized participants (11,466 women) aspirin was associated with a statistically significant 32% reduction in the risk of a first MI and a significant 15% reduction in the risk of all important vascular events, but hand no significant effects on non-fatal stroke or vascular death.
Neurology, 2002;59:880-886
Method: In 1995 to 1996 elderly (age 65+) county residents were assessed for dementia, with current and former use of NSAID, aspirin, and H2RA as well as three other “control” medication classes also noted. Three years later, interval medication histories were obtained and 104 participants with incident AD were identified among the 3,227 living participants.
Results: By contrast, former NSAID users showed substantially reduced incidence (estimated hazard ration = 42), with a trend towards greatest risk reduction among those with extended exposure. Similar patterns appeared with aspirin but not with any other medicines.
Although aspirin has been used to combat fever and pains associated with common cold for more than 100 years, its efficacy in this role was only recently confirmed in controlled clinical trials on adults. One gram of aspirin, on average, reduced the oral body temperature from 39.0 °C (102.2 °F) to 37.6 °C (99.7 °F) after three hours. The relief began after 30 minutes, and after six hours, the temperature still remained below 37.8 °C (100.0 °F). Aspirin also helped with “achiness”, discomfort, and headache, and with sore throat pain, for those who had it. The effects of aspirin were indistinguishable from those obtained using paracetamol in any respect, except for, possibly, a slightly higher incidence of sweating and gastrointestinal side-effects.
Fever and joint pain of acute rheumatic fever respond extremely well, often within three days, to high doses of aspirin. The therapy usually lasts for one to two weeks; and only in about 5% of the cases it has to continue for longer than six months. After fever and pain have subsided, the aspirin treatment is unnecessary, as it does not decrease the incidence of heart complications and residual rheumatic heart disease. In addition, the high doses of aspirin used caused liver toxicity in about 20% of the treated children, who are the majority of rheumatic fever patients, and increased the risk of their developing Reye's syndrome. Naproxen was shown to be as effective as aspirin and less toxic; due to the limited clinical experience, however, naproxen is recommended only as a second-line treatment.
Along with rheumatic fever, Kawasaki disease remains one of the few indications for aspirin use in children, although even this use has been questioned by some researchers. In the United Kingdom, the only indications for aspirin use in children and adolescents under 16 are Kawasaki disease and prevention of blood clot formation.
Aspirin is also used in the treatment of pericarditis, coronary artery disease, and acute myocardial infarction.
Taking aspirin before air travel in cramped conditions has been suggested to decrease the risk of deep-vein thrombosis (DVT). The reason for taking aspirin is the long period of sitting without exercise, not air travel itself. A large, randomized, controlled trial in 2000 of aspirin against placebo in 13,000 patients with hip fractures found “a 29% relative risk reduction in DVT with 160 mg of aspirin taken daily for five weeks. Although there are obvious problems with extrapolating the data to long-distance travelers, this is the best evidence we could find to justify aspirin use”.
The common aspirin side effects are primarily related to its anti-platelet effects. Serious bleeding, especially gastrointestinal bleeding, is the most common serious side effect. Aspirin also frequently causes gastrointestinal irritation including gastritis, gastric and duodenal ulcers, and esophagitis. These combined with the anti-platelet effect which can cause any bleeding to be more severe make GI bleeding a common aspirin side effect. Especially when used in high doses aspirin causes tinnitus, or ringing in the ears. Irreversible ototoxicity can be an aspirin side effect. The common aspirin side effects related to the anti-platelet effect include bruising and bleeding. Gastrointestinal aspirin side effect symptoms include dyspepsia, nausea, vomiting, constipation, diarrhea and abdominal pain. Aspirin can also lead to reduced excretion of uric acid and hyperuricemia. Dizziness is also common, likely related to the ototoxicity.
Serious Aspirin Side Effects: For an over the counter medication aspirin has a list of serious side effects that rival most medications available only by prescription. Aspirin allergy is reasonably common, and serious aspirin allergic side effects include anaphylaxis, angioedema, and bronchospasm. Gi bleeding can be lifethreatening, and the irreversible anti-platelet effect can make this bleeding especially difficult to manage. Bone marrow toxicity can include suppression of any of the lines of blood cells, and manifest as thrombocytopenia, agranulocytosis, and aplastic anemia, or can affect all of the blood elements as pancytopenia. Like all of the NSAIDs aspirin can cause nephrotoxicity, especially with long term high dose use. For a complete list of common and serious aspirin side effects see the manufacturers detail documents.
Unusual Aspirin Side Effects: Tinnitis is among the more unusual and yet common aspirin side effects. Nasal polyps can be caused by aspirin allergy as another unusual aspirin allergy.
Pregnancy: You must not use Aspirin during pregnancy or if you are trying to become pregnant due to possible harm to the unborn baby and interference with normal labor/delivery.
Breast-feeding: You must not use Aspirin if you are breast-feeding. Aspirin is excreted into human milk in small amounts. Peak milk salicylate levels have been reported at nine hours after maternal dosing (and measured at 1.1 mg/dL). Doses of aspirin can result in rashes, platelet abnormalities, and bleeding in nursing infants.
Aspirin should not be given to a child or teenager who has a fever, especially if the child also has flu symptoms or chicken pox. Aspirin can cause a serious and sometimes fatal condition called Reye's syndrome in children.
Stop using this medication and call your doctor at once if you have any symptoms of bleeding in your stomach or intestines. Symptoms include black, bloody, or tarry stools, and coughing up blood or vomit that looks like coffee grounds.
Avoid drinking alcohol while you are taking this medication. Alcohol may increase your risk of stomach bleeding.
Aspirin is sometimes used to treat or prevent heart attacks, strokes, and chest pain (angina). Aspirin should be used for cardiovascular conditions only under the supervision of a doctor.
Do not use this medication if you are allergic to aspirin, or if you have:
a recent history of stomach or intestinal bleeding;
a bleeding disorder such as hemophilia; or
an allergy to an NSAID (non-steroidal anti-inflammatory drug) such as Advil, Motrin, Aleve, Orudis, Indocin, Lodine, Voltaren, Toradol, Mobic, Relafen, Feldene, and others.
If you have any of these other conditions, you may need a dose adjustment or special tests to safely take aspirin:
asthma or seasonal allergies;
stomach ulcers;
liver disease;
kidney disease;
a bleeding or blood clotting disorder;
heart disease, high blood pressure, or congestive heart failure;
gout; or
nasal polyps.
If you are taking aspirin to prevent heart attack or stroke, avoid also taking ibuprofen (Advil, Motrin). Ibuprofen may make this medication less effective in protecting your heart and blood vessels. If you must use both medications, take the ibuprofen at least 8 hours before or 30 minutes after you take the aspirin (non-enteric coated form).
Tell your doctor if you are taking an antidepressant such as citalopram (Celexa), duloxetine (Cymbalta), escitalopram (Lexapro), fluoxetine (Prozac, Sarafem, Symbyax), fluvoxamine (Luvox), paroxetine (Paxil), sertraline (Zoloft), or venlafaxine (Effexor). Taking any of these drugs with aspirin may cause you to bruise or bleed easily.
Before taking this medication, tell your doctor if you are using any of the following drugs:
a blood thinner such as warfarin (Coumadin);
another salicylate such as choline salicylate and/or magnesium salicylate (Magan, Doan's, Bayer Select Backache Pain Formula, Mobidin, Arthropan, Trilisate, Tricosal), or salsalate (Disalcid).
This list is not complete and there may be other drugs that can interact with aspirin. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.
Condition: Pain, 10/26/2007 4:55:47 PM
Reviewer: 75 or over Female on Treatment for 1 to 6 months (Patient)
Comment: Taking for sciatica - works reasonably well unless buffered (passes undisolved). Have to combine with acetominophen to be very effective but can live with it.
Review by Mark P M: User Rating: 7.0, August 17, 2009 3:31 AM
aspirin for Sciatica: I am 35 year old male with moderate to severe sciatica (pain from buttock to ankle) due to bulging disc L5 - S1. I found taking a 1000mg dose gave significant and almost total relief for about 1 to 2 hours. The effect was greater if the pain was not too severe, the best results came from taking Aspirin before the pain got severe. I also found that taking Aspirin without food made it work faster but I suffered stomach aches a consequence.
Review by ... MAMA: User Rating: 10, November 14, 2008 8:24 AM
aspirin for Back Pain: It actually works.
Review by hrthota: User Rating: 9.0, December 11, 2008 12:54 AM
aspirin for Thromboembolic Stroke Prophylaxis: I have been using 150mg of aspirin everyday for the last 4 years. I have confirmed Diabetes and borderline high blood pressure. I don't find any side effects. The rest of the health parameters are okay.
Review by Renlynn: User Rating: 10, June 29, 2009 7:44 PM
aspirin for Back Pain: Have tried Motrin, Aleve, Tylenol for back pain and nothing works as well. Take it with food and take a brand that is coated and even the few side effects are lessened. It's still the safest and most effective in my personal view.
Review by Anonymous: User Rating: 9.0, July 25, 2010 9:02 AM
aspirin for Pain: This would be the second most effective NSAID for me, behind Motrin but well ahead of Aleve or other OTC's of any type - It is my preference for "cold and flu" because it breaks a fever pretty quick. If there is a downside, it's that if I take 2 or 3 a day for more than a week, it definitely causes a ringing in my ears, loud. Short-term or simple pain, the old school aspirin just works.
Review by ... man: User Rating: 10, April 8, 2008 8:34 PM
aspirin for Fever: It's awesome.
Review by olddrugs: User Rating: 9.0, July 24, 2009 12:07 PM
aspirin for Back Pain: Old and reliable.