Warfarin Use as an Area of Medicine - Research Paper Example

Alternatives to warfarin The paper examines different literature works in Warfarin use as an area of medicine. Additionally, it examines various clinical conditions that lead to individuals to use the drug as a form of therapy for their condition. Warfarin is a therapy that has been used for many years as anti-coagulant, it has been reported to be the most effective anticoagulant as compared to the others that have been developed lately. However, Warfarin has its side effects and the research paper will be seeking to study in depth on the side effects of Warfarin and ways to curb the side effects .Warfarin is a drug that is readily available in many countries not only in UK where it was first discovered. Further to that, the paper will examine the modern trends and various recorded data on the use of the therapy, and statistical data of the side effects on warfarin usage as anticoagulant. Introduction According to Patel et al. (2011), Warfarin is an oral drug widely used in United Kingdom; an oral drug is taken through the oral cavity that is the mouth. It is an anti-coagulant drug that is prescribed to individuals suffering from thrombosis. Thrombosis is a medical defect that is characterized by abnormal blood clot or coagulation of the patient blood. Hence, it is referred as anticoagulant or a blood thinner. Warfarin is used in the prevention of heart attacks and strokes. Additionally, blood clotting predominantly occurs in veins and arteries. Therefore, warfarin prevents blood clot in this part of the circulatory system. Similarly, there are people who have conditions that increase the possibility of having possibility of the blood clot developing such as atrial fibrillation. Review of Literature A study was carried out that involved 16,513 patients who had been diagnosed with Atrial fibrillation, between January 2005 and 28th February 2010. The data was obtained fro the UK Clinical Practice Research Datalink (CPRD), which was linked to Hospital Episode Statistics (HES).The data was also sourced from the National Statistics Mortality data. the individuals diagnosed with the complication were treated with Vitamin K antagonists and the consequences of atrial fibrillation monitored (Granger et al., 2011). They includes bleeding events and vascular outcomes. The intention of the research was to study the consequences that required hospitalization. The statistics were, 38% of intracranial bleeds and 6% of gastrointestinal; bleeding. The aim of the study was to explicate any future possibility of using any new anticoagulants. The results indicated there were incidences of hospitalization from the cases of bleeding.Additionally, people suffering from these complications are prescribed to use the drug Granger et al., 2011). The duration in which the drug is used depends on the purpose of prescription. However, a person must consult their health care providers to know how long to use the drug. There exist a yellow booklet given to patients that contains the details of the anticoagulants; the booklets provides information on the treatment of the defects (Granger et al., 2011). Warfarin is usually taken once in a day; it is advisable to take warfarin at the same time in different days. Blood clotting is enhanced by the presence of vitamin K in the blood, without Vitamin K blood clotting cannot take place. Therefore, warfarin functions to slow the production of vitamin K in the body. Consequently, the time taken by the blood to clot is increased and due to the delay blood clotting does not occur. Warfarin will ensure that the circulation of the blood in the body is free from any interruption, and it flows freely in the arteries, heart, and the veins. Monitoring is essential to patients under the dosage of warfarin; it is conducted once or twice a week and done using International Normalization Ratios. The ratios elucidate how long the blood takes to clot in the body. The time taken for blood to clot ranges from one person to another, the intensity of the monitoring process depends on the readings provided by the ratios. Warfarin can negatively interact with other medicines and hence care ought to be taken to avoid taking the medications that inhibit the function of with Warfarin. Additionally, certain foods and drinks can also interfere with the functioning of Warfarin. They include drinks and food rich in vitamin K; similarly it is dangerous to engage into alcoholism since it increases the possibilities of bleeding occurring. International normalization ratios indicate the time taken for blood to clot. The readings are different in different people (Schulman et al. 2013). Discussion Warfarin consumption is associated with several problems; in case a patient recognizes any of the unusual and persistent symptoms they should consult their doctors. One of the major things to avoid while under the medication of warfarin is injuries. While taking the coagulants, an injury causes a persistent bleeding; this has grave consequences. Warfarin may cause severe bleeding that is very dangerous since it can cause death. Before the doctor prescribes a patient to be using warfarin, the doctor must have the patient’s medical history. Some of the medical conditions that must be considered includes; previous blood or bleeding disorder. Similarly, the physician must consider if the patient has had any cases of bleeding problems especially I the stomach or the tube from their mouth to the stomach, bleeding in the intestines. Also Abnormal bleeding in the urinary tract, bladder and the lungs (Patel et al., 2013). Additionally, before warfarin prescription is made, the health care provider must investigate several things. Firstly, the Doctor must cross check is whether the patient has had any instance of heart attack, high blood pressure, chest pain or any heart disease. Secondly, tests on red and white blood cells count must also be done to determine their levels in the blood. Patients who are anemic tend to have different side effects from the usage of warfarin. Lastly, the doctor must also consider any cases of cancerous cells, kidney and liver diseases whether any of them has ever occurred in the patient at any time of their lives. It is advisable to inform the doctor if you have ever been faced with a major surgery or injury. Warfarin medications tend to cause bleeding to patients who are over sixty-five years old and most likely bleeding occurs in the first month of the medication process. Consequently, increased use of Warfarin or higher dosage intake may increase the possibilities of the bleeding to take place. Dosage should be taken according to the Doctors prescription; it should also be taken within the time frame as given by the physician. Additionally, individuals who engage themselves in strenuous body exercises that may cause slight injuries may also be faced with the problem of bleeding. Patients should also inform their physicians if they intend to take any un-prescribed medications such as vitamins, nutrients supplements and herbal medicines (Patel et al., 2013). Warfarin tends to react differently to other drugs. Supplements especially vitamin boosters may limit the efficacy of warfarin. A study was carried out o the Warfarin prescription using data from the National Prescription Audit Plus database of IMS Health comparing them with the complicated event reports which had been submitted to the US Food and Drug Administration (FDA). The research also focused on the study of effects of Therapeutic complications that caused deaths and bleeding caused by the use of warfarin , the data was obtained from national hospital emergency department data. The number of persons discharged from hospitals after being treated with Warfarin had increased imminently from 21 million to 31 million between the year 1998 and 2004. That translates to 45% increase of outpatients who had been discharged after successful treatment using warfarin. However, FDA report indicates that warfarin is one of the ten drugs that had caused the most adverse side effects from reports done between the year 1990 and 2000 decades. Hematologic side effects are usually characterized by occult and overt bleeding. It is referred to as hemorrhage at any site of the body. Bleeding has dire consequences such as dizziness, headaches, muscle or joint pains, paralysis, swellings, weakness and a shock from oblivion. Additionally, patients who suffer from these side effects have reported cases of hematomas, melena, hematuria, instances of epistasis and hematemesis (Herring & Shallcross, 2014). There are other bleeding complications that result from the use of warfarin, anemic complications, stomach and spinal cord bleeding. Warfarin induces two types of hemorrhage which are intracranial and extracranial. However, intracranial have is associated with most of the deaths and disabilities due to the side effects of warfarin usage. However, those people who are at a higher risk of the side effects includes; people who had a stroke in their previous years and the aged. Additionally, those people who have had previous digestive system bleeding and abuse of aspirin that is a pain killer. Additionally, there are genetic factors that cause the complications, people who have certain enzyme defects have been reported to be suffering from hemorrhage. The enzyme variations in individuals cause the medicine not to be able to slow down vitamin K when taken into the blood system. Administration of the drug has also played a role in causing the side effect, previous research have been done to investigate the various management modes available. They include oral administration anti-platelet therapy; research was carried out using the two methods. When both methods are used in administration of warfarin, tend to increase the instances of occurrence of general and gastrointestinal hemorrhage. Patients with arterial fibrillation have recorded increases in possibility of occurrence of hemorrhage as their age increases. Mostly, they are faced with intracranial hemorrhage, and this is independent of whether they are on warfarin medication or not. Visibly, eighty years and above people are more prone to the side effects than others. Intracranial hemorrhages have been associated with more than ninety percent of the total deaths that have been caused by the warfarin side effects. Dermatologic Mostly, this problem occurs in obese women who are under warfarin medication. It is referred to as Warfare-induced skin necrosis (Herring & Shallcross 2014). The conditions occur after the first ten days of the drug administration or after several months of the medication. The problem is characterized by the presence of lesions in parts that have plenty of adipose such as the skin, buttocks, breasts, abdomen and the private parts. Lesions are usually painful and cause the patients to feel upset with themselves and sharply demarcated. Warfarin induced skin necrosis is caused by an imbalance between protein S, protein C and the factors that stimulate the functioning of vitamin K..The remedy for thus side effects is discontinuation of the anticoagulant therapy; however, the formation of lesions does not stop. After several days, the patient is expected to resume the warfarin medication but I this time it must be taken in low dosages. The dosage must be administered slowly y slowly to ensure that the ratios used to determine the dosage to be administered is achieved. There have been reported cases of eyelids skin necrosis, in this instance, there are visible lesions in the eyelids that are painful (Herring & Shallcross 2014). Cardiovascular side effect are caused by embolic occlusion. It is characterized by different symptoms that include pain in the spinal cord, leg fibrosis, chest pains that are more frequent than the other symptoms. Additionally, the side effect is identified by the presence of sharp abnormal pains and back pains (Harrington, Armstrong, Nolan & Malone 2013). Hepatic side effects caused by the intake of warfarin are very rare; they are not common to patients suffering from blood clots that have been administered with the anticoagulant. They cause liver defects such as jaundice that is commonly referred to as kidney stones. Additionally, this side effect causes an irregular increase of the liver enzymes. Hepatitis can also result in this side effect; however, it is not yet clear whether they cause Hepatitis A or Hepatitis B (Herring & Shallcross 2014). Renal problems are also rare. However, if the side effects occur, it can lead to renal failure due to interstitial nephritis. Renal vessels are found in the kidney, and they may result in renal failure leading to oxidation of the body due to the failure of the detoxification system (Harrington, Armstrong, Nolan & Malone 2013). When under warfarin medication, it is necessary for the patients to change their diet; there are certain foods and drinks that the patients ought to avoid. The diet must be stable, and patients should avoid foods that are higher in vitamin K compliments such as liver and vegetables. However, they should not be permanently being misplaced from the diet but they should regularly be taken in moderate amounts. They are equally essential to healthy functioning of the body the same as the warfarin intake is critical. Several researchers have shown that drinking cranberry juice usually causes an increase in the side effects of warfarin hence should be avoided at all costs (Harrington, Armstrong, Nolan & Malone 2013). Women who are pregnant have higher chances of being faced with abnormal blood clots, these are caused by their unstable blood circulation and concentration of vitamin K in the blood. More instantly, hormonal and enzymatic changes in the body cause the side effects that have been reported. The drug has been associated with miscarriages, birth defects, and many other abnormalities. Therefore, the risks related to the warfarin taken are more than the benefits caused by the system of pregnant women.Hence, they should be avoided during pregnancy (Jung, Kwon, Park, & Moon, 2012). After birth, women can resume their taking of warfarin since there have been no cases of the drug being present in the breast milk to be consumed by their children. However, if there is any instance of children warfarin administration, it ought to be done under close monitoring. According to Harrington, Armstrong, Nolan & Malone (2013), one of the major side effects of warfarin is bleeding. Taking alcohol tend to increase the cases of bleeding mostly in the stomach. The situation can deteriorate if the patients are daily drinkers. Consumption of alcohol interferes with the drug functioning in the body.Serious allergic conditions are rare with the drug usage; however to some people it can cause slightly allergic conditions that must be reported instantly to the health care providers. The side effects include rashes, face and throat swelling, troubles in breathing and dizziness cases. Similarly, it can cause problems in the respiratory system. In the event of any problem associated with the uptake of warfarin, there are recommendations and guidelines that are outlined in the yellow card scheme. People who buy over the counter drug purchases must consult their physicians since some of the drugs cause abnormal functioning of the drug. They may also stimulate emergence of some of the side effects caused by the usage of warfarin drugs (Harrington, Armstrong, Nolan & Malone 2013). . There is no limitation of the sporting or physical activities that people under warfarin medication should participate. It is necessary to the patient to discuss with their physicians to be conversant with the games they should or they should not participate. From the previous explanations, it has been found that one of the greatest risks that faces individuals who are under warfarin medication is suffering injuries or bruises since it can cause uncontrollable bleeding. Any game or physical activity that can lead to the patients being prone to injuries should be avoided at all costs (Wang, Kong, Lee, Ng, & KO, 2014). Individuals can use protective equipment during games and physical activities. According to El-Naby, & Ismail, (2014), new anticoagulants are a new version of the drugs used to stop blood clotting in the blood vessels. They are applicable to the prevention of stroke in people who have non-valvular atrial fibrillation; this means that atrial fibrillation is not associated with any problem in a heart valve. Novel anticoagulants can also be used in the management of the clots that occurs in the veins. Therefore, there is a direct relationship between this novel anticoagulants and Warfarin. Both of them are applicable in controlling the formation of a clot in the body preventing people from cases of stroke. There are different types of novel anticoagulants; they include dabigatran, rivaroxaban, and apixaban. They are commonly found in the United Kingdom medical facilities, and they are the ones that are often used in patients who have non –valvular atrial fibrillation to help them avoid cases of stroke. There has been data collected from the hospitals emergency departments from 1999 to the year 2003 showed that warfarin was associated with about 29000 visits for complications in every year. According to the data , warfarin had recorded the highest number of complications administered into hospitals. The information confers with literature works that indicate that warfarin causes almost 10-16 % complications to those who are under its medication. Unlike warfarin that only slows down the action of Vitamin K in the blood clotting process, novel anticoagulants interfere with the most of the complex processes found in blood clotting. Due to the interruption of the complex processes, blood clotting tends to take a longer duration and consequently cases of non-valvular atrial fibrillation stroke are reduced. Interestingly, all the novel coagulants have proved to be equally important in the prevention of the blood clot despite the latter one interfering with only one process of the blood clotting. However, the main difference between the novels anticoagulants is that they are not influenced by the diets an individual takes while under medication (El-Naby, & Ismail, 2014). Therefore no need for diet change as it is evident in patients under warfarin medication. They are also not affected by other drugs that the patient may be taking. Unlike warfarin that requires close monitoring by the physicians, novel anticoagulants do not need any doctor monitoring or supervision. Upon administration of the drug, they are assured of protection from stroke and any form of the blood clot. Warfare is very sensitive and efficient when it comes to prevention of strokes. However, their effectiveness can only be possible if it is done under close monitoring by the physicians, side effects explained earlier occurs if medication of warfarin is not regularly monitored and regulated. Individuals who were using NOAC were found to be free of stroke by 19% as compared to warfarin. Side effects are different, and they depend on the type of novel anticoagulant being taken. Example is Dabigatran that has been seen to cause stomach upset to people who are under the drug medication. Across the board, one of the major side effects of anticoagulants is bleeding; this is the serious complication of the use of all the anticoagulant (Keeling et al.,2011). The probability of bleeding occurring in people using this novel anticoagulant is equal to that of those using warfarin. Bleeding in situation where an individual develops side effects as a result of the use of warfarin is manageable and controllable; however bleeding caused by the use of anticoagulants is very dangerous and unmanageable. Treatment of bleeding depends on the part where the breeding is taking place. There are various symptoms that can indicate the presence of bleeding in the body; such symptoms include regular bleeding that it is unexpected. Additionally, bruises in the skin and lashes that resembles bowel are common to such individuals, bleeding may take a long time before it stops. In such a case, the patients should report immediately to the doctor to prevent further complications that may be severe. Currently, there is no antidote that can be used to reverse the effects of novel anticoagulants (Keeling et al. 2011). However, researchers have made significant steps to development of the antidote, interestingly; there is a sample that is in the clinical trials stage that can reverse the side effects of novel anticoagulants within minutes. It was evident that high dosages of NOACs did not show a recognizable reduction in major bleeding. However it was observed that it reduced the intracranial haemorrhage. Unlike warfarin that works for a longer duration after their administration, novel anticoagulants are effective for a few hours since their administration. It is therefore, advisable that they are taken on a daily basis since if a person misses the dosage even for a single day they are assured of not being protected. However, caution must be taken to avoid taking double dosage if few hours are remaining for the next dosage. Patients should take the dose and continue as normal or wait for the right time and take the next dose (Kim et al., 2013). Double dosage increases possibilities of bleeding occurring It occurs both in warfarin and novel anticoagulants that individuals who are prone to bleeding should avoid taking them. They are both oral anticoagulants in that they are administered by the mouth. There are groups of people who have metallic heart valve, and they take anticoagulants for this condition. However, to this group of people use of anticoagulants is not recommended. To the people who suffer from different kidney impairments problems they should also avoid taking this type of anticoagulants since they may have a higher risks of bleeding. Consequently, individuals should seek their doctor’s advices to be able to know which anticoagulants are necessary for them. Doctors are always right in prescribing the right medications for such patients, one of the side effects of using warfarin is hepatic complications, the same occurs in anticoagulants usage (Kim et al., 2011). In terms of cost, novel anticoagulants are far much expensive as compared to warfarin. Despite the frequent monitoring and tests required for patients under warfarin medication, novel anticoagulants are far much expensive (Sorensen et al., 2011). Consequently, this may limit the number of people interested in being prescribed for the drug. The time of usage also matters, since the discovery of novel anticoagulants, many doctors are not aware of the scientific basis of these drugs. Previously, doctors have been prescribing the warfarin to people with cases of blood clotting problems. There is hope that as time progresses the price of the novel anticoagulants may decrease, and doctors improve their knowledge of the drug. By that time, many will opt for it as their preferred anticoagulant. Currently, statistics has shown that less than one percent of people prefer novel anticoagulants. However, many have resorted to the usage of warfarin as their anticoagulant. In the recent researches, there have been a number of novel anticoagulants that have been developed apart from the few highlighted in this paper (Herring & Shallcross, 2014). Unlike warfarin that interferes with the vitamin K in the blood to inhibit blood clotting, the newly developed anticoagulants are diverse in the processes they regulate in the complex process of blood clotting. They have been found to inhibit the functioning of the Factor Xa and inhibit thrombin factor directly. The anticoagulants are promising more than warfare since they have proved to reduce the incidences of intracranial bleeds and had more efficacy than warfarin. They are also more convenient to use by the physicians and hence they are recommended for use if they are approved later by the relevant authority. They show identical results in the management of stroke with warfarin. Lastly, if the new anticoagulants are considered and be used in the prevention of unhealthy blood clotting, they will change can improve the decisions making by clinicians. Of late, many anticoagulants have been developed; however, all of them have not met the efficacy that has been set by warfarin. Many of them are under clinical trial stage hence their usage has not been legalized by the relevant authority. Many of them are very expensive, unlike warfarin that is cheap and can be afforded by many people. In terms of medical value, warfarin is used to control harmful blood clot. Beneficial blood clotting causes bleeding to stop. Contrary to that, dangerous blood clotting can cause a heart attack, and stroke and other illnesses (Herring & Shallcross, 2014).Warfarin has been used for more than fifty years since it was developed. The history of warfarin development can be traced back in 1920s in USA when cows had developed a weird disease that was characterized by severe bleeding. The bleeding was spontaneous or would have been as a result of a slight injury. In sweet clover, it was identified that it contained hemorrhage factor that reduced the effect of prothrombin. From that discovery, many scientists have been involved until in 1948 when warfarin was developed. In 1948, it was approved by the USA government to be used in rodent trials and after a successful trial, in 1954, it was recommended for human use. Since then it has been used by more than million people (Jung, Kwon, Park, & Moon, 2012). Due to this, warfarin has been tried and tested, and it is known to be efficient and effective. Most of the newest novel anticoagulants are not understood on how they work and their efficacy have not been tried and tested. Additionally, most of the side effects are known well and the ways to control the side effects. The novel anticoagulants side effects have not been well documented since they have been in use for only a little period. Warfarin is the best medicine that we have in this world if appropriately used it is very beneficial to the patients, however if, not used well it is one of the dangerous drug in the whole world. Abnormal blood clots that are controlled by warfarin occur in the blood vessels or the heart. They can cause obstruction of the normal flow of blood in the body leading to a heart attack if they block the vessel to the heart (Granger et al., 2011).. They can also result in a stroke if it blocks a vessel to the brain. These cases have been rampant in the modern society and hence there is a need to continue using warfarin. Many of the people who are faced with these complications have not resorted to the use of warfarin and recognize its importance’s only when it is too late. The use of warfarin is made simple by its packaging. It is available in various tablets all of which have different colors and contains a label indicating the number of milligrams in every tablet. It comes with imprinted schedules of usage and the dosages, depending on the type of an individual the drug dosages may be in halves or multiple forms just to enhance efficacy of the drugs. Warfare is usually taken once per day at any time of the day. Due to these factors there is no need to neglect the usage of warfarin as an anticoagulant. There has been a developed warfarin clinic that predominantly deals with administration of warfarin to patients. However, if the use of warfarin is stopped, it means that the clinics will have nothing to offer which may translate to their closure. The clinics are run by trained health professionals who have specialized in anticoagulation; they usually possess an extensive knowledge of the warfarin usage, side effects and their efficacy (Granger et al., 2011). According to Harrington, Armstrong, Nolan & Malone (2013), in the case of Warfarin unlike other anticoagulants enables the patient to carry out an international normalization ratio measurements. The ratio is abbreviated as INR, the higher the INR, the more time required for an individual blood to form a clot. Other anticoagulants usage does not facilitate the INR tests. Healthy patients who are not under warfarin usage have INR of 1 while those who are under warfarin medications have variable readings of 2.0-3.0. Medical personnel referred to this as the target range. However, patients who have a mechanical heart valve require a target of 2.5 to 3.5. This kind of monitoring is essential to the healthy living of people. It will create an instant alarm in case there are possibility of a stroke or heart attack occurring (Harrington, Armstrong, Nolan & Malone 2013). Therefore, it is evident that the use of warfarin will continue for many years to come until there is a development of a drug that can act as thrombin inhibitor. To affirm this, there are considerations that have been put in place of late to improve the warfarin dosages. The developments are based on enacting the considerations of the genetic and environmental factors that determine the dosage to be offered to the patients (Herring & Shallcross 2014). There are environmental factors that determine the dosages administered and their efficacy includes, other drugs medications, alcoholism, and diets taken by individuals. Additionally, genetically the dosage requirements are improved by keenly studying the receptors and enzymes that are inhibited by the drug (Patel, 2013. The genes that codes for the enzymes and vitamin K are also examined in depth. There are several studies being pursued in UK and the other parts of the world to determine other genetic and non-genetic factors that determine warfarin dosages. If the studies are successful, there may emerge new and efficient clinical approaches to the administration of warfarin. Additionally, INR control can be predicted more efficiently through new algorithms that may be developed that use environmental and genetic factors as their determinants. These developments are not only important in formulating and improving a more suitable warfarin that is safe and easy and easy to use help to introduce pharmacokinetics into other areas of therapy. Conclusion Al these factors combined will ensure that warfarin will remain a force to reckon with in the field of anti-coagulants. Several years back scientists had developed a thrombosis inhibitor anticoagulant referred to as Ximelagatran (Schulman et al. 2013). However, after several years in the market it exited the market prematurely. This maintained the position of warfarin as the primary anticoagulant available in the world. In the UK only, statistics have shown that a total of 1% of the entire population and 8% of the individuals who are older than 80 years are under warfarin medication. The overwhelming increase in the number of people who uses warfarin can be traced to its effectiveness in providing therapy to embolic strokes with atrial fibrillation (Herring & Shallcross, 2014). It has proven to be efficient, and there exist a large number of documented evidences of its efficacy. To many patients where Warfarin has been used they have recorded immense positive response towards the therapy. References El-Naby, A. G. A., & Ismail, H. Y. H. G. M. (2014). Evaluation of a Designed Warfarin Educational Program on Patients’ Knowledge and Incidence of Side Effects. Global Journal of Pharmacology, 8(4), 592-600. Granger, C. B., Alexander, J. 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