- What is clopidogrel, and how does it work (mechanism of action)?
- What are the uses for clopidogrel?
- What are the side effects of clopidogrel?
- What is the dosage for clopidogrel?
- Which drugs or supplements interact with clopidogrel?
- Is clopidogrel safe to take if I'm pregnant or breastfeeding?
- What else should I know about this drug?
What is clopidogrel, and how does it work (mechanism of action)?
Clopidogrel bisulfate (Plavix) is an anti-platelet drug, that is, a drug that inhibits the ability of platelets to clump together as part of a blood clot. Clopidogrel prevents blood clots by irreversibly binding to the P2Y12 receptor on platelets, preventing adenosine diphosphate (ADP) from activating platelets. It belongs to a class of drugs called P2Y12 inhibitors. Other drugs in this class include ticagrelor (Brilinta) and prasugrel (Effient). Clopidogrel is similar to ticlopidine (Ticlid) in chemical structure and in the way it works. Unlike ticlopidine, clopidogrel bisulfate does not cause serious reductions of white cells in the blood and, therefore, routine blood testing to determine if the white blood cell count is low is not necessary during treatment. The risk of heart attacks and strokes (which usually are caused by blood clots) is increased in patients with a recent history of stroke or heart attack, and patients with peripheral vascular disease. (Peripheral vascular disease is the same as atherosclerotic arterial disease or "hardening" of the arteries in which the arteries become narrowed. It frequently occurs in the legs and often causes claudication or pain in the legs upon walking.) Clopidogrel bisulfate is used to reduce the risk of heart attacks and strokes in these patients. Clopidogrel bisulfate was approved by the FDA in 1997.
What are the uses for clopidogrel?
Clopidogrel is used for preventing strokes, heart attacks, and death in individuals who have had a previous stroke, unstable angina, heart attack or have peripheral arterial disease (PAD). The combination of clopidogrel and aspirin is better than aspirin or clopidogrel alone in preventing another heart attack but the risk of bleeding is higher.
What are the side effects of clopidogrel?
The tolerability of clopidogrel is similar to that of aspirin. The more common side effects of clopidogrel are:
- Abdominal pain
- chest pain,
- muscle aches,
- severe bleeding,
- allergic reactions,
- pancreatitis, and
- liver failure.
Ticlopidine (Ticlid) is an antiplatelet medication quite similar to clopidogrel. It has been associated with a severe reduction in white blood cell count in between 0.8% and 1% of persons. The risk of this dangerous side effect with clopidogrel is about 0.04%, much less than with ticlopidine but twice that of aspirin.
Clopidogrel rarely causes a condition called thrombotic thrombocytopenic purpura (TTP) in one out of every 250,000 people. TTP is a serious condition in which blood clots form throughout the body. Blood platelets, which participate in clotting, are consumed, and the result can be bleeding because enough platelets are no longer left to allow blood to clot normally. For comparison, the related drug, ticlodipine (Ticlid), causes TTP 17-50 times more frequently than clopidogrel.
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What is the dosage for clopidogrel?
Clopidogrel bisulfate usually is taken once daily. It can be taken with or without food. Clopidogrel is activated by enzymes in the liver to its active form. Individuals who have reduced activity of liver enzymes that activate clopidogrel due to liver disease may not adequately respond to clopidogrel. Alternative treatments should be used for these patients. The recommended dose for treating unstable angina or heart attack is 300 mg initially followed by 75 mg daily in combination with 75-325 mg of aspirin. Peripheral arterial disease or recent stroke is treated with 75 mg daily.
Which drugs or supplements interact with clopidogrel?
The combination of clopidogrel with nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Motrin, Advil, Nuprin), naproxen (Naprosyn, Aleve), diclofenac (Voltaren), etodolac (Lodine), nabumetone (Relafen), fenoprofen (Nalfon), flurbiprofen (Ansaid), indomethacin (Indocin), ketoprofen (Orudis; Oruvail), oxaprozin (Daypro), piroxicam (Feldene), sulindac (Clinoril), tolmetin (Tolectin), and mefenamic acid (Ponstel) may increase the risk of stomach and intestinal bleeding.
Combining clopidogrel with warfarin (Coumadin) or other drugs that cause bleeding increases the risk of bleeding.
Clopidogrel is converted to its active form by enzymes in the liver. Drugs that reduce the activity of these enzymes, for example, omeprazole (Prilosec, Zegerid) or esomeprazole (Nexium) may reduce the activity of clopidogrel and should not be used with clopidogrel. Other drugs that also may react with clopidogrel in a similar fashion include fluoxetine (Prozac, Sarafem), cimetidine (Tagamet), fluconazole (Diflucan), ketoconazole (Nizoral, Extina, Xolegel, Kuric), voriconazole (Vfend), ethaverine (Ethatab, Ethavex), felbamate (Felbatol), and fluvoxamine (Luvox).
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Is clopidogrel safe to take if I'm pregnant or breastfeeding?
There are no adequate studies of clopidogrel in pregnant women.
Studies in rats have shown that clopidogrel appears in breast milk; however, it is not known whether it also appears in human breast milk. Because of a potential for side effects in the nursing infant, the physician must weigh the potential benefits and possible risks before prescribing clopidogrel to nursing mothers.
What else should I know about this drug?
- Clopidogrel is avaialable as tablets: 75 and 300 mg. Tablets should be stored at room temperature, 15 C - 30 C (59 F - 86 F).
- Clopidogrel is available as a generic drug. You need a prescription from your doctor to obtain this medicine.
- Plavix is the brand name available for clopidogrel in the US.
Plavix (clopidogrel bisulfate) is an antiplatelet drug prescribed for the prevention of heart attacks and strokes in high risk individuals. Review side effects, drug interactions, warnings and precautions, and pregnancy information prior to taking this or any medication.
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Stroke is a serious medical condition. If you think you or someone you know is having a stroke call 911 immediately. There are two main types of strokes, hemorrhagic and ischemic (the most common type). A hemorrhagic stroke occurs due to a blood vessel rupture in the brain. An ischemic stroke occurs when a blood clot becomes lodged in a blood vessel in the brain, which causes a loss of blood supply to the brain, possibly causing brain tissue death. FAST is an acronym that helps people identify stroke signs and symptoms so they can act fast and call 911. Face drooping, Arm weakness, and Speech difficulty are indicators that a person may be having a stroke and it is Time to seek emergency medical treatment. Additional signs and symptoms of stroke may include weakness, difficulty walking, blurred vision, dizziness, headache, confusion, difficulty speaking, and loss of sensation. Stroke is a major cause of death and disability in the U.S. Early identification and treatment of stroke helps reduce the risk of morbidity and mortality.
A stroke is an interruption of the blood supply to part of the brain caused by either a blood clot (ischemic) or bleeding (hemorrhagic). Symptoms of a stroke may include weakness, numbness, double vision or vision loss, confusion, vertigo, difficulty speaking, or understanding speech. A physical exam, imaging tests, neurological exam, and blood tests may be used to diagnose a stroke. Treatment may include administration of clot-busting drugs, supportive care, and in some instances, neurosurgery. The risk of stroke can be reduced by controlling high blood pressure, high cholesterol, diabetes, and stopping smoking.
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Peripheral Vascular Disease
Peripheral vascular disease (PVD) refers to diseases of the blood vessels (arteries and veins) located outside the heart and brain. While there are many causes of peripheral vascular disease, doctors commonly use the term peripheral vascular disease to refer to peripheral artery disease (peripheral arterial disease, PAD), a condition that develops when the arteries that supply blood to the internal organs, arms, and legs become completely or partially blocked as a result of atherosclerosis. Peripheral artery disease symptoms include intermittent leg pain while walking, leg pain at rest, numbness in the legs or feet, and poor wound healing in the legs or feet. Treatment for peripheral artery disease include lifestyle measures, medication, angioplasty, and surgery.
Stroke vs. Mini-Stroke (TIA) Differences
A stroke occurs when a blood clot or artery ruptures within the brain. The rupture or clot causes brain cell damage or death. A mini-stroke (TIA, transient ischemic attack) is caused by brain cells that become dysfunctional over a short period. Stroke and mini-stroke warning signs of stroke and mini-stroke are the same, and include, speech problems, weakness, numbness, and facial droop. Side effects of stroke may be permanent and you may never regain full function of the parts of the body affected. Mini-stroke side effects usually resolve within minutes to a couple of days. A transient ischemic attack (mini-stroke) is a precursor for stroke because 40% of individuals who have a mini-stroke will have a stroke within a year. Treatment of stroke depends upon the type and parts of the body affected.
Heart Attack vs. Stroke Symptoms, Differences, and Similarities
Heart attack usually is caused by a clot that stops blood flow supplying oxygen to an area of heart muscle, which results in heart muscle death. Stroke or "brain attack" is caused by a loss of blood supply to the brain (usually a blood clot) or by hemorrhagic stroke (bleeding within the brain), which results in brain tissue death. Both heart attack and stroke usually come on suddenly, produce similar symptoms, can be disabling, and can be fatal. The classic symptoms and warning signs of heart attack are different. Classic heart attack warning signs are chest pain or discomfort, shortness of breath, pain that radiates to the shoulders, back, arms, belly, jaw, or teeth, sweating, fainting, and nausea and vomiting. Moreover, woman having a heart attack may have additional symptoms like abdominal pain or discomfort, dizziness, clammy skin, and moderate to severe fatigue. The classic symptoms and warning signs that a person is having a stroke are confusion or loss of consciousness, sudden severe headache, speech problems, problems seeing out of one or both eyes, and numbness or weakness of only one side of the body. Moreover, a woman having a stroke may have additional warning symptom and signs like shortness of breath, disorientation, agitation, behavioral changes, weakness, nausea, vomiting, seizures, and hiccups. Recognition of stroke symptoms is vital for emergency treatment. The acronym "FAST" stands for recognition of Facial drooping, Arm weakness, Speech difficulty, and a Time for action. If you experience the symptoms heart attack or stroke (FAST) or see them develop in another person, then contact 911 immediately.
Heart Attack vs. Heartburn
Heartburn is a symptom of another disease or medical problem and can be described as a feeling of burning in the chest accompanied by symptoms of nausea, vomiting, or a sour taste or food stuck in the back of the throat. Heart attack occurs when an artery in the heart is completely blocked by a blood clot, which causes that portion of heart muscle to die. Heart attack also has symptoms of chest pain, nausea, and vomiting, however, other warning signs and symptoms of a heart attack are unusual weakness or fatigue, and persistent and/or increased severity of symptoms over a few minutes. Heart attack is a life threatening emergency. If you think you or someone you are with is having a heart attack, call 911 immediately for urgent medical treatment. It may save your life.
Carotid Artery Disease
The term carotid artery disease refers to the narrowing of the carotid arteries and can also be called carotid stenosis. Fatty substance buildup and cholesterol deposits, called plaque are the cause of the narrowing arteries. Carotid artery disease can be treated by following recommended lifestyle changes, taking prescription medications, and considering a procedure to improve blood flow, if your doctor believes it could help.
Stroke vs Aneurysm (Differences and Similarities)
A stroke or "brain attack" is caused because blood flow to an area of the brain has been cut off by a blood clot or by a weakened or damaged blood vessel (for example, head trauma). The damaged area of the brain dies, which results in loss of function like speech capabilities, muscle movement, or muscles of an extremity like an arm or leg is reduced or lost completely. An aneurysm is a weakness in an artery wall. This weakness in the wall causes the artery to widen or balloon out, and then they rupture or break open.
Intermittent claudication, or pain and cramping in the lower leg is caused by inadequate blood flow to the leg muscles. This lack of blood flow causes a decrease in oxygen delivered to the muscles of the legs. Claudication is generally felt when walking and decreases with rest. In severe cases, claudication may be felt at rest. Narrowing of arteries cause claudication. Treatment includes exercise, medication, and in some cases surgery.
Heart Attack Treatment
A heart attack involves damage or death of part of the heart muscle due to a blood clot. The aim of heart attack treatment is to prevent or stop this damage to the heart muscle. Heart attack treatments included medications, procedures, and surgeries to protect the heart muscle against injury.
Migraine and Stroke
Migraine headache is a type of headache in which the exact cause is not known; however, they may be inherited, and certain foods and environmental factors can trigger and may contribute them. A stroke (brain attack) happens when a blood vessel in the brain leaks, bursts, or becomes blocked, which can be caused by many other health problems. Both migraines and strokes can can cause severe head pain (migraine pain usually is only on one side of the head). Migraine aura symptoms may mimic or feel like a stroke or mini-stroke (transient ischemic attack, TIA) because they have similar symptoms and signs like severe headache, numbness in the legs, feet, arms, hands, or face, nausea, vomiting, and dizziness. Other migraine aura symptoms include vision problems like flashing lights or blind spots in one eye. The main difference between migraine headache and stroke symptoms and signs is that a migraine headaches usually come on gradually while a stroke symptoms come on suddenly and unexpectedly.
Heart Attack Prevention
Heart disease and heart attacks can be prevented by leading a healthy lifestyle with diet, exercise, and stress management. Symptoms of heart attack in men and women include chest discomfort and pain in the shoulder, neck, jaw, stomach, or back.
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