Why should you be concerned about something as simple as aspirin or as complicated as anticoagulants? The answer is simple: aspirin has probably been the most widely used drug since Hippocrates’ time when he first prescribed powder ground from dried willow bark to treat headaches and arthritis pain. The powder contained salicylates, the chemical named for the ingredient in aspirin.
Not only are salicylates useful for headaches and pain, but they’re also widely used in this country and around the world as an anticoagulant in many medical conditions. Of course, there are also other anticoagulants in widespread use, and this is why they are being included in this article. Hopefully, a global picture of these will give you a better understanding of what you, your friends, and your family are or might be using for treatment or prevention of certain medical problems.
Aspirin is a NSAID (nonsteroidal anti-inflammatory drugs) along with others we know by the brand names of Motrin, Advil, Aleve, and about 20 others which are available to us generally without prescription. Both aspirin and NSAIDs are anticoagulants as well as being anti-inflammatory compounds. These two are closely linked, in that they have an effect on enzymes in your body (Cox I and Cox II), which are essential for our constant and ongoing production of prostaglandins, which control many of our body functions. If Cox I or II enzymes are inhibited, the surface of platelets becomes relatively impotent in the process of allowing blood to clot. With aspirin, it is slightly different than with other NSAIDs, but the effect is the same except for the duration of time. Aspirin prevents clotting for about a week, and NSAIDs prevent the clotting for a day or so, depending on which NSAID we are referring to.
At the same time that the aspirin and NSAIDs are affecting Cox I and II in regards to their anti-coagulant effect, they also are reducing inflammation in general in the body by reducing some of the inflammatory stimulating prostaglandins. This means that your joints feel better, your headache pain can go away, and you can even reduce the incidence of cancer and some heart problems because these conditions have their etiology associated with inflammation.
Therefore, indications for aspirin and other NSAIDs can be for pain, fever, or inflammation as well as prevention of heart blood vessel blockage and thrombotic stroke. The role of aspirin in prevention of primary heart disease has been widespread, and it has been studied extensively. Recent literature points out, however, that while you can take aspirin to prevent a first heart attack, the risk of bleeding from gastric ulcers might be slightly higher than the benefit gained from taking these. However, if you include the benefit to reducing colorectal cancer incidents and possibly decreasing your chance of getting Alzheimer’s disease, then it probably balances out pretty well. Aspirin and other NSAIDs can cause gastritis, gastric ulcer, GI bleeding, and even death from excessive bleeding. It also can cause Reye’s syndrome, which is responsible for infant deaths and is the reason that aspirin is contraindicated in children with fever and headache.
Where did salicylates and aspirin come from anyway? As mentioned, Hippocrates used this, American Indians were using a form of this when the settlers came, and many other “natural” healers have used this over the centuries. However, salicylates in its raw form caused a lot of gastric disturbance, so in 1853 a French chemist found a way to attach a small molecule called acetyl on to the salicylate becoming acetylsalicylic acid. In 1897, the Bayer Company obtained a patent for the production of something which they named aspirin and which was exactly what the French chemist in 1853 had produced. This was produced in Germany, and as part of the Treaty of Versailles in 1917, Germany opened the patent for the entire world to produce and sell aspirin as a headache and pain remedy.
In addition to aspirin, there are other anticoagulant compounds which are in wide use in this country and around the world. These include warfarin (Coumadin), heparin, and low molecular weight heparin. These compounds are specifically indicated for prevention of clotting. For example, if you have atrial fibrillation, as do three million Americans, the blood flow through the heart’s atrial chamber is filled with whirlpools and “eddies” which allow the formation of clots on the wall of the atrium. These clots can then break loose and go to the brain to cause stroke, go to the extremities to cause gangrene, or go to the intestines to cause segments of the bowl to be lost from lack of circulation. Because of this, patients are instructed to take Coumadin or some of the newer drugs which have been out for at least a couple of years and which have different actions and benefits and some advantages as well. Since these are new and in a state of early testing, I will only dwell on Coumadin.
Coumadin can be taken every day as a pill, and it prevents the liver from producing vitamin K, which is part of the whole clotting process. If you eat too many foods with a high vitamin K level, you can increase your risk for clotting, and if you take some drugs including antibiotics or Tylenol, you can increase the risk for bleeding. By testing your INR (international normalized ratio), you can determine your prothrombin level, which indicates how well or not you will make clots. Testing is straightforward, and the incidence of stroke and peripheral vascular problems is markedly decreased with this drug. Additionally, if you can eliminate the atrial fibrillation with drugs or cure it completely with ablation of the electrical sites causing the problem in the heart, you don’t have to be on Coumadin any more in the usual case. I should also mention that Coumadin is better than aspirin to prevent blood clots in this condition.
Some mention should be made of heparin and low molecular weight heparin, both of which are found in nature and are prepared for medical use to prevent coagulation. Sources for heparin include turkey, whale, bovine, porcine, and human sources. One of the problems for preparation of heparin for human use is to make certain there are no contaminants in this product. Heparin is given intravenously and must be monitored carefully to prevent overdose and complete inhibition of blood clotting. Low molecular weight heparin can be given by injection in the subcutaneous tissue and has a certain known ability to stay in the tissues for 12-24 hours and be effective as an anticoagulant. These two products are generally used for treatment of thrombophlebitis, pulmonary embolism, and for prevention of these as well. For example, after “tummy tuck” or abdominoplasty, most plastic surgeons will administer the low molecular weight heparin known as Lovenox, which helps to reduce the risk of blood clots in the legs which could travel to the lungs and cause pulmonary embolism.
Chances are that you, your friends, or your family are or have been on one or more of these so-called “blood-thinners.” It is good for you and them to have an awareness of what can happen when you are on these drugs and how they can be extremely effective in preventing medical problems, both in the perioperative time as well as long-term therapy situations.
Dr. Carraway is the director of the Plastic & Cosmetic Surgery Center of EVMS. Call 757-557-0300 for more information.