Risk Evaluation and Mitigation Strategy (REMS)

A Risk Evaluation and Mitigation Strategy is a formal programme the FDA can require, under authority granted in 2007, when labelling alone will not manage a known serious risk. The lightest form is a medication guide or a communication plan to prescribers. The heaviest is a set of elements to assure safe use, which can require certified prescribers, certified pharmacies or treatment settings, enrolment of every patient in a registry, restricted distribution, documented laboratory monitoring, or all of these together.

The archetypes are drugs whose harm is severe and preventable. Isotretinoin, a potent human teratogen, is dispensed through a pregnancy prevention programme with mandatory registration and testing. Clozapine was for decades supplied only against documented neutrophil counts because of agranulocytosis. Where generics exist, they generally have to operate within a shared system so the controls cannot be bypassed by switching product.

A programme like this changes the shape of care rather than the pharmacology. It determines who may prescribe, where a product may be dispensed and what must be documented first, which is a logistical constraint with real access consequences. It also allows approval of drugs a regulator would otherwise refuse, so its presence signals that a serious risk was judged manageable, not that the drug is uniquely dangerous.

Two inferences do not follow. The absence of such a programme is not a statement of safety; most drugs with serious warnings have none, because labelling was considered sufficient. And the controls describe the licensed supply chain only. A compound obtained outside that chain carries none of the certification, registry or monitoring requirements, which changes the oversight rather than the underlying hazard.