It starts with a text. Your sister can't sleep. Your dad's back is acting up. Could you just call something in? You can prescribe now, and saying yes feels like the least you can do. Two rules shape the answer, and the first is hiding in the DEA number on your prescriptions.
The number. If that number ends in a hyphen and a short code, the registration is not yours. It is your hospital's. A DEA rule lets a resident prescribe controlled substances under the hospital's registration instead of holding their own, with each prescriber's hospital-assigned code added to the end. The same rule allows this only within the scope of your employment at that hospital. The hospital also keeps a list matching every code to a name, available to pharmacies and law enforcement on request. Zolpidem for your sister is not part of your job. The registration does not cover it, and the code says exactly who wrote it.
If you hold your own DEA registration, that limit does not apply. Antibiotics and most other drugs need no DEA number at all. But the second rule applies to everyone, whatever the drug.
The ethics. The AMA's Code of Medical Ethics is plain: "In general, physicians should not treat themselves or members of their own families." It allows two exceptions: an emergency or isolated setting with no other qualified physician available, and "short-term, minor problems." Its reasons are practical. Your feelings can bend your judgment. You may skip the sensitive question or the intimate exam, or drift into a problem outside your training. And your relative may not feel free to turn down your advice or ask for another doctor, for fear of offending you.
Even the minor-problem exception comes with homework: document the care and tell your relative's primary care physician. The Code also warns that tension from a bad outcome "may be carried over" into your personal relationship. With your dad, a bad outcome comes home for every holiday.
None of this means leaving your family on their own. The most useful thing you can offer is help getting seen: their own doctor, an urgent care, or a telehealth visit today. Try: "I can't be your doctor, but I'll help you find one today and go over the plan with you." You stay the relative who knows medicine, which is what they wanted in the first place.
Your state medical board adds its own rules. Ohio's, for one, allows prescribing controlled substances to a family member only in a documented emergency, and its training certificate covers only program work. Read yours before the next text arrives.
Be their family. Let someone else be their doctor.