One of the most common things that I face in the office anymore is questions about medicines safety. It seems like every week, Good Morning America is telling my patients that a medicine is dangerous or has previously unknown side effects.
This past week, the TV networks were all talking about the medical study showing that taking vitamins will kill you… Now, I know that is not what that study said, but that is what most of my patients heard. Even one of my nurses was asking me if she should stop taking her multivitamins.
The vitamin study was actually designed to see if there were links between a number of things and earlier death. There was a link note in earlier death in women ages 55-65 if they took a multivitamin, but this was not a CAUSE and EFFECT study. Look at this from another angle, there could be a study done tomorrow that shows a link between eating dinner at a restaurant that serves alcohol and car wrecks, but that does not mean that eating at Outback/Red Lobster/etc will cause you to have a car wreck.
This type of study was never designed to find the cause just to note associations between incidences. This fact was so over looked by the modern news media.
Then, there are times when medicines may be deemed unsafe after a period of regular use, or have new restrictions on use. Simvastatin is a perfect example. When medicines are approved by the FDA, the drug manufacture has to prevent evidence of the medicines safety to the FDA. This means humane trials, usually double blinded placebo controlled studies. (That is the type of study where neither the doctor or patient knows if the patient is receiving the drug in question. This is the best type of study to remove most bias.) So, in human trials the drug company has to show safety data – this can be from a study on 100 people for 6 weeks to thousands of patients data for years.
These are good steps to ensure safety, however, as with simvastatin or even vioxx, once you start writing these meds for a couple of million people, doctors find out more about the medicines safety. So now simvastatin is recommended to be dosed under 40mg and under 20mg if a patient takes certain heart medicines, and vioxx was taken off the shelves all together.
I admit this is a flawed system, filled with internal bias, but it is the best we have for now. So, I implore you, the next time Katie Courick is telling you about how bad a medicine is, check her sources and get ALL the facts.
As to the link between earlier death and vitamin use, I suspect it is because people who take vitamins are more concerned with their health because of established illness, thus this represents a group more likely to die anyway. As for me, I will keep taking my vitamins till I hear of a definite causal link in a study, not just a hyped up association study.