Codeine and Children
Nov 25, 2013
By Trevor Shewfelt, Pharmacist at the Dauphin Clinic Pharmacy
What you dont know can eat you. This is the motto of the Zombie Research Society. They have useful articles on their website to prepare you for the Zombie Apocalypse. One article states a chainsaw is a poor choice of weapon to protect yourself from Zombies. A chainsaw can be difficult to start, especially under pressure. It needs to run on something like gas or electricity and during an apocalypse those will be hard to find. Finally a chainsaw is noisy. More noise attracts more Zombies. In the movie Zombieland, Woody Harrelsons character says Rule #1 to survive Zombie encounters is Cardio. The first to die are those who cant run away. Although you may be convinced the Zombie Apocalypse is not a likely threat, the folks at the Zombie Research Society would argue preparing with reliable Zombie knowledge is good for your health.
Back on June 6, 2013 Health Canada released a warning saying that pain and cough medications containing codeine are no longer recommended for children under the age of 12. Honestly I cant remember if I read that warning in June or not. If I did, it had no impact. Even when I went to a Telehealth presentation on the subject in October of 2013, I wasnt really interested. I just didnt think the subject applied to me. I really cant remember a single time I have ever dispensed a codeine product to a child. Not after a surgery, not for a bad cough, not ever as far as I can remember. Codeine and children just doesnt come up at the Dauphin Clinic Pharmacy. So I went to the video-conference talk just to get the credits I need to keep my license every year. It turns out the topic did apply to me. Apparently what you dont know can bite you in the butt.
Codeine is what we call a pro-drug. That means it doesnt do anything on its own. It has to be broken down into morphine first and the morphine does the pain killing. So what happens if something goes wrong with the enzymes that break down codeine into morphine? What happens if you are genetically predisposed to break down codeine into morphine really slowly or really quickly? That is really the crux of the whole issue.
We talk about slow metabolizers of codeine quite a bit in adult medicine. For example, we believe up to 1 in 10 of us dont convert codeine to morphine well enough for Tylenol #3 to work as a good pain killer. So just imagine that 1 in 10 people who have knee surgery could be sent home with Tylenol #3 for pain, but genetically they cant change codeine into morphine fast enough for the Tylenol #3 to be an effective pain killer. What I didnt realize was there was another genetic extreme. There are people who we call ultra- metabolizers of codeine. When they get a dose of codeine, their enzymes so full, completely and quickly change it to morphine that they get a larger dose of morphine than we expect. This doesnt really matter that much in adults. We might expect an ultra-metabolizer adult to have a little less pain, and be a little more drowsy on one dose of codeine than a normal codeine metabolizer. But when it comes to very young children who are ultra-metabolizers, the increased amount of morphine in their bodies can be enough to do damage.
The presenters of the codeine and children talk quoted a few case reports of young children, 2-5 years old, who had their tonsils out. They were given the right dose of codeine for their age and weight. However since they were ultra-metabolizers, they died because they got way too much morphine in their systems. As horrible as the death of any child is, that wasnt the part of the talk that scared me the most. Remember Ive never dispensed codeine to a child. What did scare me was what happens if the mother was an ultra-metabolizer.
It is quite common for pregnant and nursing women to be prescribed Tylenol #3. Tylenol #3 has codeine in it. My wife was on it when she was pregnant to treat migraines. It is given to women to help with pain after C-sections. The problem comes when the mom is an ultra-metabolizer of codeine. Now she converts the codeine into more morphine than expected. That morphine gets excreted into her breast milk. Unfortunately there have been case reports of neonates dying from too much morphine when mom was given codeine and was a codeine ultra-metabolizer.
Now I dont want to give the impression these unintentional overdoses due to the genetic quirk of being a codeine ultra-metabolizer are common. They are not. Codeine has been used safely in children for many years. There are only a handful of case reports of harm to children due to quick codeine metabolism. But the fact that there is a small chance of harm has convinced Health Canada to warn us not to use codeine in children under 12.
So what should we use to treat pain in children? The World Health Organization says we should start with acetaminophen and ibuprofen for mild to moderate pain. Then we should move directly to morphine for more severe pain. Morphine can still be safely dosed because it is not a pro-drug. Metabolism doesnt affect how much morphine gets into a child.
Ultra fast codeine metabolism causing harm to a child is a rare event. Codeine has been safely used in children for many, many years. But a small risk isnt the same as no risk, and being unaware of the risk doesnt keep you safe. Avoiding codeine in young children and nursing mothers is a good idea. Only knowledge of the risk and what to do instead will keep you safe. What you dont know can bite you in the butt or possibly eat you. So start some Cardio training. Then go to the Zombie Research Society to read up on why an ax is better than a sword and a .22 is better than a shot gun.
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.
We now have this and most other articles published in the Parkland Shopper on our Website. Please visit us at www.dcp.ca
Health Canada Codeine and Children warning - http://healthycanadians.gc.ca/recall-alert-rappel-avis/hc-sc/2013/33915a-eng.php#safety
Zombie Research Society - http://zombieresearchsociety.com/
Zombieland Rules - http://www.zombielandrules.com/