Aspirin approved as emergency heart attack treatment

Aspirin tablets are seen in this undated file photo. (AP / Houston Chronicle, Dave Einsel)

The first thing to do when you suspect you might be having a heart attack is to call 911. The next thing might be to take a couple of low-dose Aspirin.

Health Canada has just given Bayer Inc., the makers of Aspirin, the okay to promote their drug as an emergency treatment for heart attacks. Bayer can now state in their package inserts for low-dose Aspirin that, in the event of a suspected heart attack, users should call 911, then chew and swallow two of the tablets.

"Aspirin may help save your life if you think you are having a heart attack," the insert will read.

Aspirin 81mg is sometimes referred to as "baby aspirin." While there are generic brands of acetylsalicylic acid (ASA) -- the active drug in Aspirin -- Aspirin 81 mg is currently the only over-the-counter ASA approved in Canada to make the claim.

Dr. Alan Bell, an assistant professor in the department of Family and Community Medicine at the University of Toronto, says doctors have known for some time that ASA can lower the risk of death from a heart attack, because the drug can help stop blood clots from forming in arteries.

"For 15-plus years, we have known and have been giving patients with acute heart attacks a couple of Aspirin to chew right away," he told CTV News Channel.

"What Health Canada has done now, which is a very forward-thinking idea, is to advise we chew Aspirin at the first signs of heart attack and save that 15 minutes while you’re waiting for the paramedics arriving. And that could save your life."

Bell, who is being paid an honorarium by Bayer to speak about Aspirin, says while paramedics will usually administer ASA during a heart attack, taking the drug right away can save precious minutes.

"We know that the sooner you can get Aspirin into you, the sooner you can block the effects of these little cells in your blood called platelets," he said.

Platelets are the substances that cause blood to clot and to help stop bleeding. During a heart attack, a piece of plaque can break off the wall of an artery in the heart, signalling platelets to form a clot around the plaque. The resulting clot can block blood flow through the heart, causing a heart attack.

"Aspirin blocks the effect of platelets and hopefully improves blood flow through the coronary arteries," Bell said.

A regular aspirin contains 325 mg of ASA, while two low-dose Aspirin contain just 162 mg. Bell says that is all that’s needed to block platelets.

Users are urged to chew the Aspirin because the pills will dissolve quicker and thus be absorbed into the blood faster.

Bell acknowledged that there is a risk of causing or worsening bleeding with Aspirin, but he says that risk is low.

"And when you balance it against the benefit of taking it during that critical period that you’re having a heart attack, there’s really no issue," he said.

One heart attack occurs every seven minutes in Canada, leading to an estimated 70,000 heart attacks annually.