Because of the better understanding of fluid retention and cardiovascular effects, new medications like Avandia ( a diabetic medication), Bextra and Vioxx (pain drugs) may not have gotten approval from Food and Drug Administration, the new research shows. Those medications raised safety concerns over stroke and heart attack risks when FDA panel reviewed them.
The research was published in Hemorheology and Microcirculation. The main objects of the research were: fluid retention, blood velocity, risks of strokes, heart attacks, and their connection. This research was important since there are a lot of new medications which cause fluid retention. Now it is the main concern to make sure that medications that have been approved and now available on the U.S. market are safe for consumers. Some COX-2 inhibitors were withdrawn from the U.S. pharmaceutical market (Bextra and Vioxx) are among them. The third drug, Avandia, was not taken out of the market but was suspected in heart attack increase risks.
Effect on cardiovascular system
MS, clinical professor of family medicine at Case Western Reserve University School of Medicine, and a member of the Department of Family Medicine at University Hospitals Case Medical Center, Robert P. Blankfield, MD, who was the author of the published research, used some of hydraulic and basic cardiovascular combinations to show that fluid retention in the body is detrimental for the patient cardiovascular system. It increases the “turbulent” manner of blood flow, which leads to an atherosclerosis acceleration and so increases the risk of strokes and heart attacks.
Many drugs can cause fluid retention and increase a blood pressure rate of some patients, but doctors do not worry in most cases, if the blood pressure is not affected, but Dr. Blankfield demonstrated in his researched that it does not matter if blood pressure is higher or on the same level, because a turbulent manner of blood flow may cause fluid retention and so it is dangerous for the cardiovascular system of patient.
Dr. Blankfield states, that if FDA had been known about the risk for cardiovascular system caused by fluid retention, some medications (like those listed in the beginning) might never have been approved by FDA panel. Also, it could force FDA to review some of the policies. Blankfield added, that his research and the paper published also should help pharmaceutical companies to check if their medications are dangerous for the cardiovascular system in the first stages of medication development process. Now FDA will require verification of cardiovascular safety for new medications, designed for patients with diabetes.
Blankfield does not find the FDA response effective and it is not enough, as he thinks. He added that based on his calculations, FDA should check all the medications for cardiovascular safety, not only the new medications on market, because they can cause fluid retention as well. In his opinion, old anti-diabetic medications (like sulfonylureas and insulin) can be a reason for fluid retention and so should be reviewed once again, unlike some of the new medications (saxagliptin) for diabetes treatment which cannot cause fluid retention. It would be helpful if pharmaceutical manufacturers will careful when presenting their medications on the market if the medications can cause fluid retention without affecting blood pressure.
Also, he pointed out that it is possible to reduce the risk of heart attack and strokes if patients who take medications with fluid retention effect (even withdrawn from the market ones: Avandia, Vioxx) would take also a diuretic (also known as “water pill”) medication. It is important to know that fluid retention increases stroke volume in some patients and increases blood pressure in others but medications that could increase those risks also prevent strokes and heart attacks, when they used to treat high blood pressure.
The research by Dr. Blankfield can be useful not only for public health and pharmaceutical companies but also for food manufacturers and FDA. Blankfield’s analysis showed that fluid retention could be caused not only by medications but also by sodium chloride also known as “table salt” to most of the people. FDA should consider this information and since table salt is the food additive, there should be a warning label placed, telling about increased risk of strokes and heart attacks may be caused by increasing of table salt amount in food.
In the conclusion, Blankfield’s analysis showed the work of the cardiovascular system in details, so pharmaceutical companies can use his mathematical analysis in their products design and for identification of cardiovascular risks of their medications. Now It will be even simpler for pharmaceutical manufacturers to predict the rate of the risk by using two basic principles of hydraulics and hemodynamics.
FDA is now able to make sure, that medications that can cause fluid retention but not affect blood pressure are safe for consumers simply by reviewing the information collected from pharmaceutical manufacturers. Also, FDA can now review their policy regarding withdrawn medications and bring them back on the market, but with providing health care professionals with the information about safety use of those medications with diuretics in cases, if those medications were highly beneficial in other ways.