People have been chewing on willow tree bark to get at the precursor of aspirin for its medicinal properties since the time of Hippocrates. The ultimate derivative, which we call aspirin, was synthesized to improve its effectiveness. It was marketed as a miracle curative, but eventually became best known for its pain-relieving properties. As synthetic alternatives for pain relief have become available, aspirin has taken a backseat, but the health benefits of low dose aspirin therapy continue to be debated. Recent studies appear to substantiate its use as a preventative, rather than to treat acute conditions.
What Is Low Dose Aspirin Therapy?
Records show that Hippocrates recommended a number of materials be given to patients for pain relief, one of which was willow bark. The advice was sound, and doctors of the day adopted the practice, making willow bark a standard treatment. As alchemy evolved into modern-day chemistry, aspiring chemists eventually isolated the active ingredient, which was known by the common name salicin. Further refinement eliminated the inactive portions of the molecule, yielding salicylic acid, which was more effective than salicin, but had a greater tendency for a number of undesirable side effects. Eventually, it was learned that further processing could reduce those tendencies, and the end-result was acetylsalicylic acid, which is the chemical name for modern-day aspirin.
It has been suggested that salicylic acid, which is the active portion of aspirin, may be important enough to warrant giving it status as a vitamin. Known colloquially as “vitamin S”, salicylic acid and its derivatives find widespread use in human health, including topical pain relief (liniments), acne treatments, psoriasis, and warts. Taken internally, it reduces fever, inflammation, and generalized pain. Its consumption is recommended for heart attack and stroke sufferers, to reduce the potential for blood clotting, and it also finds use in food preparation, as an antiseptic and preservative.
Aspirin is categorized as a non-steroidal anti-inflammatory drug, putting it in the same class of compounds as ibuprofen. Early studies on the activity of aspirin lead researchers to believe it blocked the production of prostaglandins, which are involved in many processes within the body, including: clotting, smooth muscle contraction, hormone regulation, inflammation, pain transmission, cell growth, and regulating body temperature (i.e. fever). Later studies showed that aspirin doesn’t actually work against prostaglandin directly, but instead works against the molecule cyclooxygenase, which converts arachadonic acid into prostaglandin, as well as inhibiting the production of thromboxane. Aspirin, ibuprofen, and naproxen are all COX inhibitors, in that they work against both of the known cyclooxygenase molecules, called creatively COX-1 and COX-2.
A standard dose of aspirin for acute treatment in the U.S. is generally given in 325-mg tablets, and low dose aspirin therapy is generally about 25% of that, coming in 75-81-mg tablets. As of the time of this writing, the U.S. Preventative Services Task Force recommends aspirin as a protect against myocardial infarction in certain at risk groups. In a 2007 statement, the Task Force issued a statement recommending against its use to prevent colorectal cancer, while more recent studies have shown higher aspirin doses to be effective at reducing the risk of certain inherited forms of colorectal cancer. Other research has linked regular aspirin consumption with reduced risk of a whole array of cancers, including prostrate, breast, esophageal, stomach, and lungs.
Regular aspirin therapy isn’t without its downsides, and making the decision to start it should be done with a doctor’s supervision. Salicylic acid has been shown to bind to, and damage, the lining of the stomach, thereby increasing the risk of gastrointestinal bleeding. Individuals with kidney disease can be at increased risk of renal failure, and low dose aspirin therapy has even been shown to increase the risk of drug-induced hearing loss.
The decision to engage in low dose aspirin therapy has a number of potential upsides, but there are no guarantees, and it doesn’t come without risks. If its something you’re considering, talk to your doctor to help make the best decision based on your situation.
Published October 2011. Updated November 2011.
References
- “Daily Aspirin Therapy” Mayoclinic.com. Accessed November 2011.
- “Low-dose Aspirin Therapy For Cardiovascular Prevention” Medscape.com. Accessed November 2011.
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