The majority of new medicines are more dangerous than pre-marketing testing predicts. Of 198 new drugs marketed between 1976 and 1985, 102(51.5%) caused toxic effects that required the drugs to be either re-labeled or withdrawn, according to the U.S. General Accounting Office.
By federal regulation, drugs are tested in animals and in human volunteers. But problems of extrapolating results from animals to humans, combined with the near-impossibility of finding relatively rare toxic effects in small volunteer samples, renders pre-market testing a dicey proposition at best.
Zomax was a common pain-killer in the early 1980’s. But it had to be withdrawn when it caused 14 deaths and hundreds of life-threatening allergic reactions. Nomifensine was a new antidepressant that was supposed to be less toxic ,than others. After several patients became ill and some died, nomifensine was withdrawn.
The irony is that most new drugs are not medically necessary. Drug manufacturers are as competitive as automobile manufacturers. If one has a patent on a certain medication, competitors develop similar medications that compete for a share of the market. Take Valium, for example, a best-seller for Roche pharmaceuticals. It was used for anxiety reduction, sleep, alcohol-withdrawal, and any numbers of other indications, and sales soared. Because Valium was patented, it could not be copied or produced generically. But with minor modifications, new Valium-like drugs appeared on the market, now numbering in the dozens. Dalmane, Halcion, Serax, Ativan, Xanax, and many others boast of a shorter or longer duration of action or a slightly different side-effect profile. But in the GAO’s review of new drugs that turned out to be toxic, of eighteen Valium-like compounds, three raised additional problems after approval.
What does all this mean to the consumer? Unfortunately, it means that unpredictable side-effects will often occur. The true range of effects of new drugs becomes evident only after they are in widespread use. And the research and development required even for unnecessary new drugs means millions of dollars that will ultimately have to come from the consumer, animals killed in gruesome toxicity tests, and human volunteers exposed to potential risks – all for products that have more to do with business competition than medicine.
And for every drug which fails or which is withdrawn, millions of dollars of research and development costs are defrayed by padding the prices of the company’s remaining drugs.
Reprinted from Good Medicine, Winter 1993, published by Physicians Committee for Responsible Medicine (PCRM).