Scientific evidence, rather than uncontrolled case studies should be the basis for patient management

The case study and review article by Mill and colleagues published in this volume of Therapeutic Advances in Drug Safety reaches a potentially dangerous conclusion that puts patient belief ahead of scientific evidence. The authors report on a case study in which the patient was convinced that they require a lactose-free preparation. The authors present a very admirable review of the research literature that demonstrated that lactose-intolerant individuals can easily tolerate the small amounts of lactose found as an excipient in pharmaceutical preparations.1–3 In fact, the level of tolerance is likely 30-fold higher than the highest amount of lactose found in a single capsule (12 g of tolerance versus 400 mg).4 Mill and colleagues consider that the nocebo effect (the worsening of symptoms following the administration of a placebo, in this case the small amount of lactose found in the pharmaceutical) might be at work