Pradaxa, A New Drug, Be Careful

Drug ads are now filling commercial time on most television programs. On the evening news the other night,  I watched an ad for a new drug, Pradaxa, which is supposed to "sometimes" take the place of Coumadin for people with chronic atrial fibrillation. Sounds like a real advance, mainly because Coumadin is a "terrible" drug. It requires constant (monthly) monitoring to avoid serious complications, and it interacts with just about everything we consume, including other drugs. Frankly, it's dangerous, and I have personally witnessed complications in patients. So Pradaxa may, I say MAY, be the answer to replace Coumadin. We must just wait and see.  Unfortunately, we need to wait until a multitude of patients use it to really see what it does.

There is an expression in the medical field that applies to Pradaxa, “Be sure to use the new drugs early while they still work.” This might sound strange, but there are real reasons for this insightful statement.

Do you remember Fen-Phen? It was introduced in the mid 90s as a weight loss drug, and many flocked to its promise, because we are almost all overweight. Turns out, that by 2004, the FDA pulled it off the market. Further experience with it revealed that it caused pulmonary hypertension, and heart valve problems. Legal damages have amounted to $13 billion, and Wyeth—the unfortunate pharmaceutical company that marketed it—has allegedly put away another $21 billion for other potential legal problems.

How about Vioxx ,which had 80 million users at one time. This drug was introduced in the 1990s as a Cox 2 inhibitor that helps with chronic pain syndromes. This drug was withdrawn in 2004 because it apparently significantly increased the incidence of myocardial infarction and strokes in patients. As of March, 2006, there had been 10,000 lawsuits, and 190 class action law suits filed against Merck.  Are we beginning to see a pattern?

Another drug that deserves mention is  Avandia a relatively “new” diabetes drug. In September 2010, the NY Times reported that this drug was “banned in two European countries.” One study reported that from 1999-2009, claimed 47,000 people needlessly suffered heart attacks because of this drug. Apparently, the use of this drug has now been highly restricted.

I guess this history of unintended side effects makes me uncomfortable when I see TV adds for new drugs. Pradaxa may eventually work well, but the fact is we just don’t know.

"Using the new drugs early..." makes sense, because once millions begin to use them, side effects may become evident that were not discovered in the clinical trials, and some of those “effects” can be serious.

The human body is complex and delicate, and putting chemicals into it, and into the cell, can have effects that don’t become evident for a time. If we imagine the complexity of the cell, with its multiple interrelated chemical reactions, and the delicate balance of these reactions, we can begin to understand why there might be some untoward side effects when we “tamper” with this chemistry. My guess is that we only measure a few of the effects of medicines, and that there are possibly other effects that we don’t completely understand or know about. Those “side effects”  are the ones that show up over time when enough people begin to use a “new” drug.

As a physician, I have great respect for the pharmaceutical industry. It has brilliant scientists working for it, and it has given us many life saving drugs that have stood the test of time. There have been some pit falls along the way, but name an industry that has not had them.

Pradaxa may turn out to be just what we are looking for to replace the unpredictable and precarious Coumadin drug we are currently using. I hope it is. But it is a “new” drug, and even if I needed it, I might stick to the old stand-by, and wait and see what Pradaxa really does to our bodies.