Sometimes when I surf the net looking for things to write about I run across things I don’t ordinarily write about but attract my attention because they are especially pertinent to my own health. Here’s an example. I recently herniated a disk, for which I took fairly hefty doses of anti-inflammatories. Mostly it was extra strength aspirin but often it was horse doses of ibuprofen. I am also of the age that it makes sense to take low dose aspirin for its anti-platelet effects. There is good data to suggest this is a preventative for heart attack and stroke. Now it turns out I may have been nullifying the heart benefits when I took the ibuprofen:
Stroke patients who use ibuprofen for arthritis pain or other conditions while taking aspirin to reduce the risk of a second stroke undermine aspirin’s ability to act as an anti-platelet agent, researchers at the University at Buffalo have shown. In a group of patients seen by physicians at two offices of the Dent Neurologic Institute, 28 patients were identified as taking both aspirin and ibuprofen [Motrin, Advil] (a nonsteroidal anti-inflammatory drug, or NSAID) daily and all were found to have no anti-platelet effect from their daily aspirin. Thirteen of these patients were being seen because they had a second stroke/TIA while taking aspirin and a NSAID, and were platelet non-responsive to aspirin (aspirin resistant) at the time of that stroke. The researchers found that when 18 of the 28 patients returned for a second neurological visit after discontinuing NSAID use and were tested again, all had regained their aspirin sensitivity and its ability to prevent blood platelets from aggregating and blocking arteries. The study is the first to show the clinical consequences of the aspirin/NSAID interaction in patients being treated for prevention of a second stroke, and presents a possible explanation of the mechanism of action.
The Food and Drug Administration currently warns that ibuprofen might make aspirin less effective, but states that the clinical implications of the interaction have not been evaluated. “This interaction between aspirin and ibuprofen or prescription NSAID’s is one of the best-known, but well-kept secrets in stroke medicine,” said Francis M. Gengo, Pharm.D., lead researcher on the study. “It’s unfortunate that clinicians and patients often are unaware of this interaction. Whatever number of patients who have had strokes because of the interaction between aspirin and NSAIDs, those strokes were preventable.” (HPNOnline)
It was a pretty well kept secret from me, I will admit. It turns out that there is an interesting time-action effect here. Both ibuprofen and aspirin will interfere with platelet aggregation for 4 – 6 hours when taken alone or with aspirin. This is the good effect, the one that inhibits clot formation. That means if you take the combo once a day or ibuprofen alone you are unprotected for the remaining 75% of the 24 hour cycle. But a dose of aspirin alone will affect platelet aggregation for 72 – 96 hours. The effect apparently doesn’t cumulate or else we would all bleed out on daily dosing.
Gengo, the lead researcher of the UB study, made another interesting observation. Aspirin is pretty cheap but if you want to pay a lot more for pretty much the same protection, Big Pharma has a solution. They make a drug, Aggrenox, designed for stroke patients to prevent a subsequent stroke, precisely the situation studied here. This expensive item is a combination of aspirin and an extended release agent, dipyridamole, that does the same thing. The combo is alleged to be slightly better, on average, than aspirin alone, but the dipyramole has a common side effect when people start taking it. It causes a headache. According to Gengo:
” . . . some physicians, pharmacists or physician assistants tell patients to take a Motrin so they don’t get a headache. This likely would negate the effects of the aspirin and extended release dipyridamole. Those patients might as well take this expensive drug and flush it down the toilet.”
Even flushing it down the toilet does some good, however. It still enriches Big Pharma and may make the drug available to the rest of us at no cost — in our drinking water.