Some things just DON’T go together. Like oil and water…ice cream and ketchup… or pancakes and mustard.
Some medicines just don’t go together either, and can cause serious problems if they’re combined. When 2 drugs should NOT be taken by the same person, it is considered a drug-drug interaction.
One example of a drug-drug interaction is adding a blood thinner medicine to another blood thinner medicine. The most common side effect of taking blood thinner medicines is bleeding, and taking more than one blood thinner at a time increases the possibility of having unusual bruising, a nosebleed, stomach bleeding or even bleeding into a joint.
In general, blood thinner medicines such as aspirin, warfarin (also Coumadin®), Plavix® (also clopidogrel) and newer ones like Pradaxa®, Eliquis® or Xarelto® should NOT be taken together unless your doctor specifically instructs you to do it. However, sometimes it’s necessary to take more than one blood thinner at a time in order to prevent blood clots.
Pain medicines with anti-inflammatory action like ibuprofen or naproxen can relieve muscle pain, swelling and stiffness better than acetaminophen (Tylenol®). These medicines are called NSAIDs, which is short for non-steroidal anti-inflammatory drugs. Aspirin, naproxen and ibuprofen are the most widely used NSAID medicines because they are available without a prescription. I often recommend naproxen or ibuprofen to relieve muscle aches, swelling, dental pain and menstrual cramps.
One of the most common side effects of an NSAID medicine is bruising and bleeding. If you are already taking a blood thinner and then start taking an NSAID for your headache or backache, it increases the chance you will have serious bleeding. Both NSAIDs and blood thinner medicines can cause bleeding, and taking them together increases the risk. But how much does it do that?
Doctors have known for some time that taking an NSAID medicine while on a blood thinner could increase the risk of having bleeding, but it wasn’t very clear how much. A new study published earlier this month looked at the bleeding risk associated with taking an NSAID together with a blood thinner.
The researchers asked themselves, how much does taking an NSAID affect the chances of having serious bleeding when taken by someone who is already on a blood thinner? To answer this, they looked at bleeding events in two trials: the EINSTEIN-PE trial, with people diagnosed with blood clots in their lung, and the EINSTEIN-DVT trial, with those diagnosed with a blood clot in their leg. Both groups were taking a blood thinner for their clot, either warfarin (Coumadin®) or Xarelto®.
Although all the study participants were cautioned that taking an NSAID could increase the likelihood of them having bleeding, 25% of them did take an NSAIDs during the trial, and those who did had significantly more serious bleeding. The researchers were surprised to find out how much bleeding. Those who took an NSAID were 2.5 times more likely to have a serious bleeding episode and 25% of those bleeding episodes occurred within only eight days of taking the NSAID.
Aspirin, ibuprofen (Motrin®, Motrin-IB®), and naproxen (Aleve®) are the most common NSAIDs because they don’t require a prescription. You can also be prescribed a prescription NSAID medicine for a back strain or dental procedure.
Can you safely take just ONE dose of an NSAID if you are already taking a blood thinner? Possibly. In my mediguide Taking Warfarin Safely I talk about what you can safely take for aches and pains while taking the blood thinner warfarin. It explains, “Occasional use (2 to 3 times a week) of naproxen or ibuprofen for muscle aches or dental pain is usually safe unless you have had stomach bleeding or an ulcer”.
With this new information about increased bleeding risk, if you take a blood thinner then having one dose of an NSAID no more than 2-3 times a week is probably still reasonable. It would be safer for you to avoid taking naproxen or ibuprofen whenever possible and instead substitute acetaminophen (Tylenol®) for aches and pains. Because some things just DON’T go together. Like NSAIDs and blood thinners…chocolate and pepperoni…grapefruit juice and milk…pickles and peanut butter…
