An article in the New York Times’ Upshot section earlier this month noted that the US Food and Drug Administration (FDA) is now approving drugs with an almost routine swiftness. Special programs originally designed to expedite the passage to market of treatments for life-threatening or rare diseases have gradually encompassed the majority of drugs in development. According to the Times, “Most new drugs qualify for special F.D.A. approval.”

Efficient drug-approval is important, as the Ebola crisis showed: the technologies for ZMapp, a cocktail of antibodies that treat the disease, had in the words of one scientist, “been around for a few decades” by 2014, but ZMapp had still failed to get through the FDA process and was not available in sufficient quantities to tackle last year’s devastating outbreak. And anyone who has known someone suffering from a rare illness will be familiar with the anguish of not having access to a cure and the willingness to try therapies, however unproven, that offer hope.

Yet caution is, of course, warranted. Arthur Daemmrich, an associate professor at the University of Kansas School of Medicine, has studied the history of the drug-lag debate in the US. He traces policymakers’ oscillation between a desire to protect patients from potentially ineffective or harmful therapies—epitomized in the thalidomide disaster—and the wish to offer them every potential avenue to improve and prolong their lives.

It was a doctor and university professor, William Wardell, Daemmrich writes, who first coined the term “drug lag,” in 1972. His research, conducted with a colleague, showed that the US trailed France by one year, Germany by 1.6 years, and the UK by 2.1 years in approving new medicines. The Aids crisis and associated patient activism were key factors in pushing the FDA to reduce the time its process took. Larry Kramer, the playwright and activist, accused the FDA of being “the single most incomprehensible bottleneck in American bureaucratic history,” and “actually prolonging the roll call of death.” During the 1990’s accelerated approval plans were instituted, and by 1999, Daemmrich says, the US had caught up with Europe.

Today, with the US no longer lagging behind, the need to tread carefully is more important than ever. Some new drugs are “me too” products that mirror without bettering the efficacy of therapies already available. Patient safety rightly remains crucial, and comments on the New York Times report indicate public unease. In their arguments for a speedier FDA, activist groups of the 1980’s and 90’s spoke of the patient as informed and knowledgeable, an individual who, as Daemmrich puts it, “to borrow a term common to economics and political science—is a sophisticated, ‘rational actor’ who can review medical information and make informed decisions.” As a result, the responsibility for evaluating the risks of certain treatments shifted away from regulators and towards individual doctors and their patients.

In fact, such a portrayal of the patient belies the informational asymmetry inherent in healthcare, particularly in such a vast and complex ecosystem as that of the US. Regardless of how intelligent a patient is, it will be a challenge to gain access to and then wade through the data needed to compare one treatment with another or assess the effectiveness of a new drug; an even more difficult task to accomplish when one is critically ill.

The regulation of pharmaceuticals in the US appears to have rotated from tardiness to speed. Yet both have the potential to harm or even kill patients who may already be seriously unwell. Given the multiple interests involved, an FDA focus on quickly approving the drugs that are truly additive and effective would be the most fruitful route.

The views and opinions expressed in this article are those of the authors and do not necessarily reflect the views of The Economist Intelligence Unit Limited (EIU) or any other member of The Economist Group. The Economist Group (including the EIU) cannot accept any responsibility or liability for reliance by any person on this article or any of the information, opinions or conclusions set out in the article.