The FDA regulates medical device safety and effectiveness. Something that is safe and effective if used one way can most certainly be unsafe or ineffective if used in another way. Viagra as a treatment for erectile dysfunction? Safe and effective. Viagra as a treatment for low blood pressure? Extremely unsafe and the opposite of effective.

And specifically, the law restricting the FDA from regulating the practice of medicine reads:

> Nothing in this chapter shall be construed to
limit or interfere with the authority of a health
care practitioner to prescribe or administer any
legally marketed device to a patient for any
condition or disease within a legitimate health
care practitioner-patient relationship. This
section shall not limit any existing authority of
the Secretary to establish and enforce
restrictions on the sale or distribution, or in the
labeling, of a device that are part of a
determination of substantial equivalence,
established as a condition of approval, or
promulgated through regulations.

While this clearly leaves open the option for general off-label use, I don't read this as barring the FDA from limiting a specific form of off-label use.

The decision also relies on some peculiar interpretations of language - for example it recognizes that the FDA has the right to impose use-specific restrictions on a device, but does not consider a ban to be a subcategory of restriction. And reading the definition of device which is intended to distinguish between a device used for medicine vs one that is not (which obviously ties a device's classification to how it is utilized) as implying use is irrelevant simply because the word disease is not explicitly singular seems absurd. Consider a test that distinguishes bacterial from viral infections - it doesn't make sense to label it as a separate device for every single viral and bacterial disease, but that doesn't mean it's use is irrelevant.

And an important point from the dissent:

> The devices, for instance, can be used to treat smoking
addiction. When used for that purpose, the agency found, the
devices present a different, and acceptable, benefit-risk profile.
Id. at 13,317. That is in part because a smoker typically
controls the device and can stop its use when it causes undue
pain, and she can also communicate any harmful symptoms to
a healthcare provider. Id. By contrast, persons with
intellectual or developmental disabilities receiving treatment
for self-injurious or aggressive behaviors often do not control
the electrical stimulation devices they wear (rather, the devices
are controlled by a third party or automatically trigger upon
detecting certain movements). Id.; Proposed Rule, 81 Fed.
Reg. at 24,394, 24,396. Those persons also may lack the ability
to discern a causal connection between the devices and
physical or psychological harm, or may be unable to
communicate the harmful symptoms to others.

It's not just what they're using the device for, it's how the device is physically designed to be used. Imagine a defibrillator that instead of going off when an operator pushes a button, instead goes off at random intervals. Imagine a medical radiation source with its radiation shield that controls dosage removed. Imagine an anesthetic delivery system that delivered the same amount of anesthetic to every patient regardless of their physiology. Changing how a device is controlled changes the device, and the FDA should most certainly have the power to ban devices with clearly unsafe or ineffective control schemes.

I very strongly agree with the dissenting opinion on this one, and I hope this ruling gets overturned.