Perhaps the most widely used drug in human history, aspirin has received terrible press in the last few months. Prescribed often by doctors since it was first invented in the 1890s, it has some remarkable properties. It is anti-inflammatory, which helps people with arthritis. It is given to patients after they have heart attacks or strokes or after having heart procedures such as stents or bypass surgery to prevent another cardiac event. It relieves pain, lowers fever, and can make blood less sticky. Studies have even linked aspirin to a decreased chance of getting colon cancer.

So, why the bad rap? Recent large-scale trials, known as ARRIVE, ASCEND, and ASPREE (names more suggestive of science-fiction movies than clinical trials), have suggested that taking aspirin might do more harm than good.

All these trials looked at low-dose aspirin (100 mg per day) given to people without known cardiac disease, compared aspirin directly with a placebo pill, and had the goal of finding out whether taking daily aspirin prevented problems in the future. ARRIVE found aspirin had no benefit in preventing heart problems but led to a higher risk of bleeding. ASPREE gave aspirin to the elderly, who were more than 70 years old when they started the five-year trial. Not only did aspirin not prolong life compared with a placebo, it unexpectedly was associated with a higher risk of dying from cancer. ASCEND looked at people with diabetes and found a 12 percent decrease in the rate of vascular events, but at the cost of a 29 percent increase in serious bleeding events.

So clearly, there may be a problem with this low-cost miracle drug. How can the new information be reconciled with the tradition of taking aspirin to help almost everything?  Following are my suggestions, based on available studies, about who should take it and who should not:

  • If you have had a heart attack, stent, or bypass surgery, an aspirin every day for the rest of your life can help prevent another cardiac event. This is called secondary prevention, and there is no doubt that daily aspirin helps. Continue to take aspirin and do not stop (even prior to a scheduled surgery) unless ordered to do so by your doctor.
  • If you are more than 70 years old and do not have a heart problem, do not take daily aspirin. Taking it preventively will not make you live longer. Don't take it to prevent cancer, as we do not know whether it helps or hurts.
  • If you have diabetes but have not had a cardiac problem, taking aspirin will significantly increase your risk of bleeding.
  • Aspirin is not for kids and should never be given to children. In the late 1970s, St Joseph's Aspirin for Children — the chewable orange-flavored form of aspirin — was linked to a rare but often-fatal childhood illness called Reye's syndrome.
  • At this time, no one knows if the best dose of aspirin for secondary prevention is low-dose (defined as 81 to 100 mg) or regular-dose (325 mg). A study is ongoing to help figure out the correct dose, and we should know this answer soon.
  • If you have had stroke or a cardiac stent, doctors sometimes use aspirin or another kind of blood thinner, called Plavix. They are often used together. Check with your doctor if you are not sure whether you should be on both.
  • If you take daily low-dose aspirin for secondary prevention, it works by making platelets in your blood less sticky. Medications called non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, can interfere with the effects of aspirin.  Take your aspirin at least 30 minutes before taking an NSAID, or wait to take your aspirin at least six hours after taking an NSAID.
  • Occasional aspirin use is safe for adults for fever, pain, or other discomfort. New information about potential harm is limited to daily preventive use.
  • Low-dose aspirin is often enteric-coated. Absorption is delayed until the aspirin has left the stomach. This makes it quite a bit more expensive. It might be best to lose the coating and save some money, as coating may actually prevent absorption and make your aspirin less effective.
  • The bottom line: These new trials are the last three strikes for preventive aspirin treatment. Unless you have heart or vascular disease or have had stroke, no matter your age, there is a good chance that taking it daily will not help you and may actually be harmful.

David Becker, M.D., is a frequent Inquirer contributor and a board-certified cardiologist with Chestnut Hill Temple Cardiology in Flourtown. He has been in practice for 25 years.