The Dangers of Cayenne for Heart Attacks and Strokes

I have recently seen several dangerous recommendations given concerning recommendations for cayenne pepper for people on Coumadin (Warfarin) and for people having a stroke.  I want to address these statements since they do consist of dangerous advice.
The first claim was that because cayenne pepper is a blood coagulant that it would be safe to take with the powerful blood thinner Coumadin.
To start with it is not really true that cayenne is a blood coagulant if taken internally.  This myth stems from the fact that cayenne pepper can stop bleeding of minor wounds if applied topically.  Does this mean that cayenne is a blood coagulant? Not really.  The fact is that basically any herbal powder, even blood thinning herbs, applied topically will stop bleeding of minor wounds.  The reason has nothing to do with the phytochemicals in the plant, but rather has to do with their cellulose content.  Cellulose in many plant fibers makes an excellent substrate for blood to coagulate on.  I worked with a guy many years ago who was working on a patent for cellulose bandages because of this simple principle.  By using bandages made of pure cellulose this would provide a substrate for blood from wounds to immediately coagulate on to stop the bleeding.
This DOES NOT mean that cayenne will work in the same manner within the body.  To begin with, cellulose is not even absorbed by the body.  Instead the cellulose is fermented in the colon by the flora to generate beneficial acids, peroxides, bactericides and vitamins.  What is absorbed from the cayenne in to the bloodstream are the natural blood thinning salicylate (aspirin) compounds, which are present in very high levels in cayenne.
Coumadin is an extremely dangerous drug on its own to begin with.  And it interacts with many foods and other medications.  Foods and food additives that Coumadin interacts adversely with include coagulating and blood thinning compounds.  Foods high in vitamin K, such as dark green leafy vegetables, are contradicted with Coumadin because they interfere with the effects of Coumadin.  Foods and additives that thin the blood present even more of a problem.  These include cayenne, ginger, sweet woodruff, vanilla, etc.  There are some other herbs and supplements that also need to avoided when on Coumadin such as clovers, lomatium, dong quai (angelica root), willow bark, pansies, fish oil, etc.
To really understand why blood thinning compounds are so dangerous to use while taking Coumadin, it is important to first understand a few things about Coumadin.  Coumadin was originally discovered by the Wisconsin Agricultural Research Foundation (WARF) leading to the original name for Coumadin of Warfarin.  The drug was discovered after cows feeding on hay that had been rained on started dropping dead suddenly.  When the cows were autopsied it was found that the cows had died from internal hemorrhaging.  It was later discovered that what lead to the internal hemorrhaging were the ingestion of powerful blood thinning dicoumarins.  The hay itself contained some sweet clover that normally contains mild blood thinning coumarins.  As the hay got wet from the rain though, the hay started to ferment.  This changed the milder coumarins in to very strong blood thinning dicoumarins. Coumadin is an example of these dicoumarins.
We know that dicoumarins are potent blood thinners, which makes them extremely dangerous for use to begin with due to the potential for death from uncontrolled hemorrhage.  But there is more to the dangers of Coumadin though.  Coumadin not only thins the blood, but it also thins out tissues including blood vessels.  If you ever knew anyone on Coumadin you may have noticed that even the slightest bump in to something generally results in tearing of the skin and major bruising.  This is from the thinning effects of Coumadin on tissues such as the skin and blood vessels.  The thinning effect on blood vessels is of the most concern since this increases the risk of blood vessels rupturing leading to uncontrolled hemorrhage.
I have always found it interesting that when researching the side effects of Coumadin in the Physician’s Desk Reference that there is no mention of hemorrhagic stroke listed as a side effect.  Instead, the closest they get to mentioning this fact is the statement that Coumadin can cause uncontrolled hemorrhage from any organ in the body.  Of course “any organ” includes the brain. 
Because Coumadin is frequently prescribed to prevent stroke though the drug manufacturers do not want any mention of Coumadin causing strokes.  There are various forms of stroke though.  Strokes can come from thrombus, embolus, hemorrhage or hypotension.  Coumadin only helps prevent thrombic strokes, but not other forms.  In addition, as mentioned previously Coumadin significantly increases the risk of hemorrhagic stroke.  The reason for this is two fold. First of all, Coumadin can thin arteries in the brain making them more prone to rupturing.  Secondly, if an artery in the brain does rupture from Coumadin thinning then hemorrhagic stroke can occur as the Coumadin interferes with the normal clotting process leading to the uncontrolled bleeding within the brain.  Even a small hole or tear in the artery will lead to uncontrolled bleeding in to the skull.  Since there is no natural way for the increasing pressure to be relieved from the bleed the increasing pressure starts compressing the brain leading to a stroke.
This is one of the reasons that patients must be tested frequently for their ability to clot when on Coumadin.  In some cases the blood needs to be thinned to prevent blood clots from forming.  At the same time though it is important that the blood is not thinned out too much since this can possibly lead to a hemorrhagic stroke or death from uncontrolled bleeding.
Maintaining proper Coumadin levels is difficult though since as mentioned previously Coumadin reacts adversely to so many foods, additives and other drugs.  One food that can adversely interact with Coumadin is cayenne pepper since ingesting cayenne provides blood thinning salicylates that increase the blood thinning effects of Coumadin.  Thus cayenne pepper can also increase the dangerous side effects of Coumadin.
This leads to my first point of contention to people recommending cayenne pepper for someone having a stroke.  A person having a stroke may have a previous history of strokes.  Since Coumadin is frequently given to people who have a history of stroke it is important to know if someone is taking Coumadin to begin with before telling them to take cayenne pepper at all, and especially when they are having a potential stroke.

The reason I said “potential stroke” is because aneurysms can also mimic a stroke.  Why is it so important to differentiate between the two?  Because a ruptured aneurysm can cause someone to bleed to death quickly if not operated on right away.  Taking a blood thinner such as cayenne can not only increase the rate of bleeding from a ruptured aneurysm, but it can also increase the risk of hemorrhage during surgery.
Another issue is that as I pointed out earlier there are different forms of stroke.  There is no way though to simply look at a person and tell what kind of a stroke they are having.  If the person has a hemorrhagic stroke then thinning the blood by taking cayenne will only make things worse.  Not only from the initial bleeding, but it can again also increase the risk of hemorrhage during the required surgery.
Another issue with taking cayenne pepper during a stroke is the reason it is recommended, which is to dilate blood vessels.  Actually this poses two problems.  But I want to clear up a major misconception about cayenne pepper first.

It is often claimed that cayenne pepper helps to increase circulation.  Although this is true it is still misleading.  Cayenne pepper is effective in dilating the smaller superficial blood vessels in the body, but is not very effective in dilating the larger primary blood vessels in the body.  Herbs such as prickly ash bark or butcher’s broom are much more effective in dilating the larger primary blood vessels and have longer lasting effects than cayenne pepper.  The primary dilation of the smaller superficial blood vessels by cayenne actually has a positive and a negative aspect when it comes to strokes.
The positive is that it does not have much of an effect on dilating the primary blood vessels in the event of a rupture of a major blood vessel.  This is important since clotting of blood is not the only way in which the body controls bleeding.  Another method by which bleeding is controlled is by constriction of blood vessels that reduces blood flow.  Therefore, if cayenne were to dilate a major blood vessel significantly when it develops a bleed the dilating effect would further increase the rate of bleeding.
The negative is that the dilation of the smaller blood vessels could still lead to uncontrolled hemorrhage if the person is on other blood thinners.
If the person is not used to ingesting cayenne or the cayenne has a very high heat unit value then this can also pose a problem.  The pain of suddenly ingesting hot pepper can further aggravate the issue as this would increase anxiety and lead to an increased release of epinephrine (adrenaline) speeding up the heart while actually reducing flow to the heart and brain.  During a heart attack or stroke this would increase the death of tissues.
If continuing to take cayenne during and right after a heart attack or stroke then there is an increased risk of another problem, known as reperfusion injuries.  When the blood supply is cut off from tissues long enough tissue death occurs from a lack of oxygen. Examples of this are seen with heart attacks and strokes.  When the blood supply is then restored this sets off a series of events that lead to inflammation and tissue destruction in part from oxidative damage from the increase of blood and oxygen back to the tissues.  People recommending taking cayenne pepper during a heart attack or stroke recommend doing this to increase circulation to the heart or brain.  This can in theory increase the risk of damage from reperfusion injuries by increasing blood flow to the dead tissues.
Due to the various risks that cayenne pepper poses during a heart attack or stroke I have to strongly recommend AGAINST this practice.