New Drug Warnings Require Vigilance

If you’ve ever watched TV commercials for drugs like Viagra, Vioxx or Zocor, you know that they present such medications in a very appealing light. Actors smile and seem to be having such a wonderful time that it is little wonder millions of Americans remember these names and ask their doctors for a prescription.
A voice-over may present side effects in a few seconds while the images on the screen continue to be upbeat. It’s hard to pay attention to brief warnings when people appear to be having fun.
But the televised cautions are just the tip of the iceberg. Open the doctors’ drug bible, the Physicians’ Desk Reference, and you’ll discover that almost all medications come with a long list of potential side effects, interactions and contraindications.
Even more alarming is the growing awareness that such lists are often incomplete. Potentially serious adverse effects may be discovered years after a new drug is introduced.
Take Vioxx, for example. This popular pain reliever was recently linked to an increased risk of heart attacks. When Vioxx was approved, physicians thought it would be far safer than existing arthritis medicines because it was less likely to cause ulcers.
The new data on heart attacks may force physicians to re-evaluate its overall safety. It is unlikely that this controversy will ever make it to a 30-second TV commercial.
Another thorny issue involves antidepressants and children. Drugs like Prozac and Zoloft have been prescribed to kids for decades. But it is only within the past few years that the FDA began to examine whether such drugs might increase suicidal thoughts or actions.
Now physicians will have to weigh the benefits and risks of such medications more carefully. And families will need to keep a close watch on youngsters taking such drugs.
All these warnings can create information overload. A busy doctor may not be able to keep up with all of the new adverse effects and drug interactions that are being discovered.
Most physicians know that drugs for erectile dysfunction like Cialis, Levitra and Viagra don’t mix well with heart medicine like nitroglycerin. They may not be aware that alpha-blocker drugs, prescribed for high blood pressure or enlarged prostate, can also pose problems. Such medications [Cardura (doxazosin), Hytrin (terazosin) or Minipress (prazosin)] may cause blood pressure to go too low if taken with a medication for erectile dysfunction like Cialis or Levitra.
How do doctors learn about newly discovered complications? There is no organized system to keep physicians up to speed. If the problem is serious enough, the FDA may require a drug company to send out a “Dear Doctor” letter with details about the problem.
But past experience with the allergy pill Seldane and the heartburn medicine Propulsid suggests that such letters are easily overlooked. These products had to be removed from the market because repeated warnings about drug interactions did not change prescribing behavior.
When busy doctors have too little time to check on new side effects or interactions, patients need to be extra vigilant. Families should enlist the pharmacist to help them stay abreast of any new developments involving their medicines.