Stroke is a sudden loss of brain function caused by the interruption of blood flow to the brain, as a result of either an ischemic stroke (a blood clot) or a hemorrhagic stroke (a rupture of a blood vessel and bleeding into or around the brain). Approximately 80% of strokes are ischemic and 20% are hemorrhagic.


When the blood supply is interrupted, brain cells begin to die without oxygen-rich blood. If the blood supply is not restored soon, the affected part of the brain dies, causing disability or death. Stroke is a leading cause of disability, with about 300,000 Canadians living with the effects of a stroke. Approximately 60% of people who have had a stroke are left with some form of disability such as paralysis, sensory loss, memory loss, language problems, or vision problems.



An ischemic stroke results from a blockage in blood flow to the brain by a blood clot. The buildup of plaque in the artery wall (atherosclerosis or "hardening of the arteries") is an underlying cause for many ischemic strokes.

A hemorrhagic stroke is caused by bleeding into the brain (intracerebral hemorrhage) or bleeding around the brain. Brain hemorrhages may result from uncontrolled high blood pressure, or in some cases can be caused by structural problems within the blood vessels (such as aneurysms).



Age: Risk of stroke increases with advancing age.

Ethnicity: People of First Nations, African, Hispanic, and South Asian descent have greater rates of high blood pressure and diabetes, which can increase the risk of stroke.

Family history: Risk of stroke may be higher if a parent or sibling has had a stroke before age 65.

Gender: Men have a higher risk than women who have not reached menopause.

Prior stroke or transient ischemic attack (TIA): Up to 33% of people who survive a first stroke or TIA will have another within 5 years.



1. High blood pressure:

Blood pressure that is consistently higher than 140/90 is considered high. If you are diabetic, higher than 130/80 is considered high.

2. High Cholesterol:

LDL is low-density lipoprotein and is considered the "bad" cholesterol. HDL is high-density lipoprotein, which is considered the "good" cholesterol. Too much LDL contributes to the buildup of plaque in the artery walls which can lead to a stroke. Lowering your cholesterol can dramatically reduce your risk of heart disease and stroke.

3. Heart Disease or Atrial Fibrillation (A-fib):

Atrial fibrillation is a condition which involves an arrhythmia (irregular heartbeat). It is the most common type of arrhythmia, in which the heartbeat is often very fast and irregular. One of the main complications of A-fib is stroke. A person with A-fib has a risk of stroke that is 3 to 5 times higher than an individual without Atrial fibrillation.

4. Diabetes:

Diabetes increases the risk of high blood pressure, atherosclerosis (narrowing of the arteries), coronary artery disease and stroke. This is especially true if the blood sugars are poorly controlled.

5. Physical Inactivity and being overweight:

Over 60% of Canadians are either overweight or obese. This is a concern as being overweight or obese is a major risk factor for heart disease and stroke. By achieving and maintaining a healthy weight, the risk of heart disease and stroke is drastically reduced.

6. Cigarette Smoking:

Smoking as well as being exposed to second-hand smoke has many negative health effects, but in particular, the risk of developing heart disease or stroke is dramatically increased. Smoking contributes to the buildup of plaque in the arteries, increases the likelihood of a blood clot, reduces the oxygen in the blood, increases blood pressure, and makes the heart work harder. Smoking nearly doubles the risk of an ischemic stroke.

7. High Alcohol Intake:

Drinking too much of any kind of alcohol can increase blood pressure and can lead to heart disease or stroke. Never drink and drive. Never drink alcohol if you are taking drugs that interact with alcohol such as narcotics, antihistamines, tranquilizers, and many more medications about which you can ask your pharmacist.

8. Stress:

Too much stress can increase the risk of heart disease and/or stroke. Some people with high levels (or prolonged levels) of stress may have higher cholesterol, higher blood pressure or may be more likely to develop atherosclerosis. Long term exposure to stress can lead to anxiety or depression as well.



The symptoms of stroke appear suddenly, over a few minutes or hours, or at most a couple of days. Seek immediate medical attention if any one of the 5 main symptoms of stroke occur:

* sudden paralysis or numbness of the face, arm or leg (usually on only one side of the body)

* sudden loss of speech or trouble understanding speech

* sudden loss of vision (often in only one eye) or double vision.

* sudden dizziness or loss of balance or coordination.

* sudden severe & unusual headache (often described as "the worst headache of my life" that starts suddenly with no known cause.


Recognizing these symptoms can be critical, as medical attention must be sought out immediately. In order to prevent brain damage, disability and to aid recovery, treatment must be started within the first few hours following a stroke. Brain cells that are deprived of blood flow (and oxygen) for a few minutes will die.

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Take the F.A.S.T. Test:

ACT "FAST" because the F.A.S.T. test can identify up to 89% of strokes or TIA's and is an easy way to recognize and to remember the key signs of stroke and what to do.

F Facial weakness (has the mouth drooped?)

A Arm & leg weakness (can the person raise both arms?)

S Speech problems (is speech slurred/can the person understand you?)

T Time is critical.

If you or someone that you witness have any one of these symptoms, call 911 immediately!


A Transient Ischemic Attack (TIA) is a "mini-stroke" caused by a temporary interruption of blood flow to the brain. The symptoms of a TIA are the same as those for a stroke (see above), except the symptoms disappear within a few minutes to hours. Medical treatment is required with a TIA as a TIA can be a warning that you may be at risk of having a stroke in the future.


MEDICATIONS to treat stroke:

Short-term treatments include 2 types of injections:

1.Thrombolytics such as tPA (tissue plasminogen activator), which aims to break up a blockage and often should be used within 3 hours after the onset of symptoms.

2. Anticoagulants such as heparin.

Long-term treatments which are taken by mouth to reduce the risk of recurrent strokes:

1. Anticoagulants, or "blood thinners", such as Warfarin or Dabigatran.

2. Antiplatelets , such as Acetylsalicylic Acid (ASA), Clopidogrel, Dipyridamole, Ticlopidine.



Warfarin belongs to the class of drugs known as anticoagulants. Many people refer to warfarin as a "blood thinner" although it does not actually thin the blood. Warfarin helps to prevent blood clots from forming or from getting bigger. Warfarin is used to prevent blood clots for people with conditions that put them at increased risk of developing blood clots such as abnormal heart rhythms (Atrial fibrillation), leg circulation problems, or after surgical procedures or trauma.

The dose of warfarin is individualized according to blood clotting time which is determined by a lab test, called an INR which is performed at regular intervals. It is very important to keep your lab appointments since there is a narrow range between too much and too little of the medication. Too much warfarin may cause you to bleed more easily, whereas too little warfarin may lead to harmful blood clots forming.

The following drugs can interfere with warfarin: acetaminophen, alcohol, allopurinol, amiodarone, ASA (aspirin),"azole" antifungals (eg. fluconazole, ketoconazole), celecoxib, clarithromycin, fluoxetine, garlic, ginkgo biloba, ginseng, ibuprofen (Advil ), methyl salicylate (A535 Rub), non-steroidal anti-inflammatories (NSAIDS, such as celecoxib, ibuprofen, naproxen), prednisone, St.John's Wort, and Vitamin K. For a complete list and for the significance of these interactions, talk with your pharmacist.


Dabigatran belongs to the anticoagulant family. Dabigatran is used to prevent blood clots for people who have had total hip replacement or total knee replacement surgery. It is also used to prevent stroke or blood clots in people with atrial fibrillation.

There may be an interaction between dabigatran and drugs such as ASA, amiodaraone, clarithromycin, clopidogrel (Plavix), grapefruit juice, heparin, ketoconazole, NSAIDS (non-steroidal anti-inflammatories like celcoxib, ibuprofen, naproxen), and warfarin. Talk to your pharmacist for a complete list.

In March, 2012, Health Canada issued an "advisory" regarding new information concerning dabigatran (Pradax). See Health Canada's website,


ACETYLSALICYLIC ACID (ASA) (eg. Aspirin, Entrophen):

Acetylsalicylic acid has four different ways of working, and therefore belongs to several different groups of medications: analgesics (pain relievers), antipyretics (fever reducers), anti-inflammatories (inflammation reducers), and platelet aggregation inhibitors (anticlotting agents). Because of the antiplatelet (anticlotting) properties of ASA, it may be used under a physician's supervision to:

- prevent a first non-fatal heart attack in people who are at increased risk of having a heart attack (factors that increase the risk of heart attack include: smoking, high blood pressure, high cholesterol, inactive lifestyle, stress, and being overweight).

- prevent a second heart attack.

- reduce the risk of "mini-stroke" (transient ischemic attack, or TIA).

- reduce the clotting properties of platelets for people who have had carotid artery surgery, and for people who are receiving hemodialysis through a silicone rubber access.

- prevent blood clots for people who have had a total hip replacement.

Check with your pharmacist regarding medications that can interact with ASA, as there are many interacting substances such as anticoagulants (like warfarin or heparin), nonsteroidal anti-inflammatories (such as ibuprofen, naproxen and others), methotrexate, vaccine for chicken pox, and more. It is important to talk with your doctor or pharmacist about any possible interacting drugs, because the significance of these interactions must be determined by a health care professional who can weigh the benefits versus any possible risk. Some interactions are easily managed by monitoring; others can be dangerous.



Clopidogrel belongs to the class of drugs known as antiplatelets or platelet aggregation inhibitors. Clopidogrel is used to help prevent heart attacks, strokes and other circulation problems in people who have atherosclereosis (narrowed blood vessels due to "hardening of the arteries") and have already experienced at least one atherothrombotic event such as heart attack, stroke, or diagnosed peripheral arterial disease. It is also used along with ASA (acetylsalicylic acid) by patients with acute coronary syndrome or atrial fibrillation (fast irregular heartbeat, as mentioned earlier in this article).

Normally, platelets help the clotting of the blood after injury; however, in a patient who has fat deposits (plaque) in the arteries (due to too much "bad" cholesterol), platelets can often clump together in the blood vessels. Unstable plaques can rupture, which leads to more clumping of platelets which then can cause larger blockages of an artery. This further narrows the artery and can lead to a heart attack or stroke. Clopidogrel reduces the chance of these events happening by preventing the clumping of platelets.

There may be interactions between clopidogrel and ASA (acetylsalicylic acid), antacids, fluoxetine, ginger, ginkgo biloba, ketoconazole, non-steroidal anti-inflammatories (like ibuprofen, naproxen and others), warfarin, and more. As discussed above (regarding ASA), some interactions can be managed by your doctor and pharmacist, as some interactions may be intentional and desirable; however, other interactions can be dangerous. Please discuss these issues of managing multiple medications with your pharmacist.

In September, 2011, Health Canada issued new information regarding clopidogrel (Plavix) in an advisory. Visit Health Canada's website at



To reduce your risk of stroke, modify your lifestyle:

* stop smoking tobacco

* increase your level of physical activity

* maintain a well-balanced diet

* limit your intake of alcohol

* maintain a healthy weight

* manage stress in your life

* if you have high blood pressure, take your medications regularly to keep it under control

* if you have high cholesterol, watch your diet and take your cholesterol-lowering medications regularly.

* we have only discussed a few of the most common medications used, so if you have any questions talk with your doctor or pharmacist.

Much of the above information has been taken from or as well as from See also or


Philip A. Smith, B.Sc.Phm.