Aspirin vs. Plavix (clopidogrel)

• Aspirin and Plavix (clopidogrel bisulfate) are drugs used to prevent blood clots.
• Aspirin and Plavix belong to different drug classes. Plavix is an anticoagulant and aspirin is a nonsteroidal anti-inflammatory drug (NSAID).
• Aspirin also is used to reduce fever, and to treat pain and inflammation in the body.
• Side effects of Plavix and aspirin that are similar include:
• Abdominal pain/burning sensation/cramping, and liver damage or failure.
• Side effects of Plavix that are different from aspirin include:
  • Diarrhea
  • Rash
  • Itching
  • Headache
  • Chest pain
  • Muscle aches
  • Dizziness
  • Severe bleeding
  • Allergic reactions
  • Pancreatitis
• Side effects of aspirin that are different from Plavix include:
  • Ringing in the ears (tinnitus)
  • Gastrointestinal ulcers or bleeding
  • Nausea
  • Gastritis
• Aspirin and Plavix are more effective when taken together, but it increases the risk of bleeding.
• Brand names for aspirin include Bayer and Ecotrin. Aspirin is available over-the-counter (OTC) and in generic form.

What is aspirin? How does it work?

Aspirin is a nonsteroidal anti-inflammatory drug (NSAID) used to treat fever, pain, and inflammation in the body. It also prevents blood clots and is used to prevent heart attack and stroke. Other NSAIDs include ibuprofen (Aleve, Motrin), indomethacin (Indocin), and nabumetone (Relafen).

NSAIDs block the enzyme that makes prostaglandins (cyclooxygenase), resulting in lower concentrations of prostaglandins, and reducing levels of inflammation, pain, and fever. Inhibition of prostaglandins also reduces the function of platelets and the ability of blood to clot. Aspirin inhibits the function of platelets in a manner different from other NSAIDs and its antithrombotic effects last longer than other NSAIDs.

What is Plavix? How does it work?

Plavix (clopidogrel bisulfate) is an anti-platelet drug used to prevent blood clots. Plavix is used to reduce the risk of heart attacks and strokes, particularly in people with a recent history of stroke or heart attack, and those with peripheral vascular disease.

Plavix works by 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 P2Y12 inhibitors include ticagrelor (Brilinta) and prasugrel (Effient). Clopidogrel is similar to ticlopidine (Ticlid) in chemical structure and in the way it works.

Aspirin uses

Aspirin is used for the treatment of inflammation, fever, and pain due to from many forms of arthritis, including:

• Rheumatoid arthritis
• Juvenile rheumatoid arthritis
• Systemic lupus erythematosus
• Ankylosing spondylitis
• Reiter's syndrome
• Osteoarthritis
• Soft tissue injuries, such as tendinitis and bursitis

Aspirin also is used for rapid relief of mild to moderate pain and fever in other inflammatory conditions. Because aspirin inhibits the function of platelets for prolonged periods, it is used for reducing the risk of another stroke or heart attack in people who have already had a stroke or heart attack.

Plavix uses

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.

Aspirin side effects

Most people benefit from aspirin and other NSAIDs with few side effects. However, serious side effects can occur and generally tend to be dose-related. Therefore, it is advisable to use the lowest effective dose to minimize side effects.

The most common side effects of aspirin involve the gastrointestinal system and ringing in the ears.

Gastrointestinal side effects of aspirin

• Ulcers
• Abdominal burning
• Pain
• Cramping
• Nausea
• Gastritis
• Serious gastrointestinal bleeding
• Liver toxicity

Sometimes, ulceration and bleeding can occur without any abdominal pain. Black tarry stools, weakness, and dizziness upon standing may be the only signs of internal bleeding.

The daily dose of aspirin should be reduced if you have ringing in the ears (tinnitus).

Other side effects of aspirin include:

• Rash
• Kidney impairment
• Vertigo
• Dizziness

Other side effects and adverse reactions of aspirin

• People with peptic ulcers or poor kidney function should avoid taking aspirin since it can aggravate both conditions.
• Aspirin may exacerbate asthma.
• Aspirin can raise the blood uric acid level and is avoided in patients with hyperuricemia and gout.
• Children and teenagers should avoid aspirin for symptoms of the flu or chickenpox because of the associated risk of Reye's syndrome, a serious disease of the liver and nervous system that can lead to coma and death.
• Aspirin can increase the effect of medicines used to treat diabetes mellitus, resulting in abnormally low blood sugars if blood sugar levels are not monitored.

NSAIDs should be discontinued prior to elective surgery because of a mild tendency to interfere with blood clotting. Aspirin, because of its prolonged effect on platelets, is best discontinued at least ten to fourteen days in advance of the procedure.

Plavix side effects

The tolerability of clopidogrel is similar to that of aspirin. Common side effects of clopidogrel are:

• Diarrhea
• Rash
• Itching
• Abdominal Pain
• Headache
• Chest Pain
• Muscle aches
• Dizziness

Side effects of Plavix that are more serious include:

• Severe bleeding
• Allergic reactions
• Pancreatitis
• 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, ticlopidine (Ticlid), causes TTP 17-50 times more frequently than clopidogrel.

Aspirin dosage

• You should take aspirin with food. Doses range from 50 mg to 6000 mg daily depending on the use.
• Usual doses for mild to moderate pain are 350 or 650 mg every 4 hours or 500 mg every 6 hours.
• Doses for rheumatoid arthritis include 500 mg every 4-6 hours; 650 mg every 4 hours; 1000 mg every 4-6 hours; 1950 mg twice daily.
• Heart attacks are prevented with 75, 81, 162, or 325 mg daily.
• 160 to 325 mg of non-enteric coated aspirin should be chewed immediately when experiencing symptoms of a heart attack.
• The dose for preventing another stroke is 75 to 100 mg daily.

Plavix dosage

• Clopidogrel bisulfate usually is taken once daily.
• Plavix can be taken with or without food.
• Clopidogrel is activated by enzymes in the liver to its active form. People who have reduced activity of liver enzymes that activate clopidogrel due to liver disease may not respond adequately 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.

Aspirin drug interactions

Aspirin is associated with several suspected or probable interactions that affect the action of other drugs. Examples of the most common of the suspected interactions include:

• NSAIDs may increase the blood levels of lithium (Eskalith, Lithobid) by reducing the excretion of lithium by the kidneys. Increased levels of lithium may lead to lithium toxicity.
• Aspirin may reduce the blood pressure lowering effects of blood pressure medications. This may occur because prostaglandins have a role in the regulation of blood pressure.
• When aspirin is used in combination with methotrexate (Rheumatrex, Trexall) or aminoglycoside antibiotics (for example, gentamicin) the blood levels of the methotrexate or aminoglycoside may increase, presumably because their elimination from the body is reduced. This may lead to more methotrexate or aminoglycoside-related side effects.

Individuals taking oral blood thinners or anticoagulants, for example, warfarin, (Coumadin) should avoid aspirin because aspirin also thins the blood, and excessive blood thinning may lead to serious bleeding.

Plavix drug interactions

• The combination of clopidogrel with nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin increase the risk of stomach and intestinal bleeding.  Other NSAIDs include 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).

Aspirin safety

• Aspirin is generally avoided during pregnancy because it may adversely effect the fetus. However, low aspirin doses have been safely used for the prevention of complications of pregnancy.
• Aspirin is excreted into breast milk and may cause adverse effects in the infant.

Plavix safety

• 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.