I hate epilepsy drug levels.
Other neurologists know what I’m talking about: Dilantin, Tegretol, and Depakote are the main ones we deal with. Levels for newer medications aren’t checked much, and phenobarbital is fading into the background.
I rarely check levels because 90% of the time they’re immaterial. If the patient isn’t having seizures and isn’t having side effects, who cares what the level is? It’s obviously just right for that patient (sort of like Goldilocks) regardless of what a number tells me it is.
Certainly there are exceptions to this: the well-controlled patient who suddenly goes downhill, for example. But in most cases, routinely checking drug levels serves no purpose, and often causes more harm them good.
In medical school, I was taught that you should never order a test unless the results will affect your plan of care. In a stable seizure patient, are you going to base your medication adjustments on how they’re doing, or a number?
Worse still, these levels are often used by specialties that don’t understand them. How many times have you seen well-controlled patients who had an unneeded level ordered – along with their annual lipid profile or thyroid panel, or because they went to the emergency department with pneumonia – and then had a nonneurologist adjust their dose based solely on the result? You often don’t find out about it until the patient calls you to report they seized or are suddenly drug-toxic.
I’m not an internist. In fact, I stink at general medicine, and don’t even pretend to understand the many drugs they have to start, adjust, and stop on an everyday basis. I don’t expect them to know as much about seizure medications as I do, anymore than they expect me to understand treatments for hypertension or diabetes. So I tell my patients that unless it’s an emergency, don’t let anyone else adjust their seizure medications. Just have them fax me the lab report, and I’ll deal with it.
At first, I was afraid this approach would ruffle feathers, but it hasn’t. Local internists have told me they’re glad to be able to take something off their list of concerns and punt it to me.
Modern medicine is full of things we can do, even when they’re just minor drug levels from a lab. But it’s still important to focus on what we should do, and to me, routinely checking drug levels should always be questioned.
Dr. Block has a solo neurology practice in Scottsdale, Ariz.