TOO MUCH ACETAMINOPHEN?

By Trevor Shewfelt, Pharmacist at the Dauphin Clinic Pharmacy

Have you heard Trevor on the radio? Listen to 730 CKDM Tuesday Mornings at 8:35 am! We now have most of the articles published in the Parkland Shopper on our Website www.dcp.ca

The information in this article is intended as a helpful guide only. It is not intended to be used as a substitute for professional advice. If you have any questions about your medications and what is right for you see your doctor, pharmacist or other health care professional.

In my line of work, dose is very important. Warfarin can stop a blood clot from giving you a stroke. This is good. Too much warfarin can make your brain bleed and cause a stroke. This is bad. “A little of this is good, more must be better,” definitely doesn’t apply to medications. If you take enough of anything it can be bad for you. Did you know you can drink enough water to cause swelling of the brain? The same goes for acetaminophen or Tylenol. We consider acetaminophen a very safe medication. However, too much acetaminophen can be harmful. In fact the FDA in the US is considering new regulations to limit the doses of acetaminophen.

Acetaminophen is used for pain and fever, but it does not reduce inflammation. Acetaminophen is less irritating to the stomach than some other over the counter products like ibuprofen, naproxen sodium or asa. Acetaminophen is found in many, many products. It can be a single ingredient like in Tylenol or in combination with other medications. Combination products include many cough and cold products, sinsus products, and pain medications like robaxacet. Also many prescription products like Tylenol #3 and Percocet have acetaminophen in them too. So you can see how it would not be difficult to accidentally take two or more products all with acetaminophen in them and so get too much.

If you take too much acetaminophen it can damage the liver and kidneys. Acetaminophen is usually metabolized by the liver. Your liver breaks it down into non-harmful chemicals and excretes it. If you take too much acetaminophen the usual metabolic pathway gets overwhelmed and the acetaminophen is broken down by another pathway which leads to a poisonous product. Some of the symptoms of acetaminophen poisoning are loss of appetite, nausea, vomiting, stomach pain, confusion, yellowing of the skin and eyes, coma and even possibly death.

At the end June 2009 a sub-committee at the Food and Drug Administration (FDA) in the US made some recommendations to the FDA about acetaminophen. They recommended prescription products with acetaminophen and other painkillers should be pulled off the market. The panel recommended that the daily maximum of acetaminophen should be lower than its current 4 grams (although they didn’t say what it should be). The panel would like the single dose maximum of acetaminophen to be reduced from 1000 mg to 650 mg. The panel would like 1000 mg of acetaminophen to only be available by prescription. However the panel rejected the idea of pulling cough and cold products that contain acetaminophen.

Now the FDA doesn’t have to follow the panel’s recommendations. But especially with the acetaminophen and strong painkiller combination prescription drugs, the panel cites that 60% of acetaminophen deaths are due to prescription products. Acetaminophen remains the leading cause of liver failure in the US despite years of warnings. And the panel says acetaminophen sends 56,000 people to the emergency room in the US every year.

Canada obviously doesn’t have to follow the decisions made by another country. But it will be interesting to see what Health Canada has to stay after studying the FDA decision. Will 1000 mg of acetaminophen become a prescription product? That could make for a whole lot of people needing to see their doctor in an already over-taxed health care system. Will medications like Percocet be pulled off the market? If yes, what will replace them? Oxycontin? It is effective, but has some issues with some people abusing or selling it. NSAID’s? They are effective, but will we now get more ulcers and kidney disease?

I think the answer should be for people to read their bottles of medication more carefully and ask their pharmacist before they take medications together. The FDA would argue we have been telling people that for years and it hasn’t helped. But does it make sense to take away useful drugs instead of coming up with better educational campaigns?

As always if you have any questions or concerns about these or other products, ask your pharmacist.