I was given a diagnosis of epilepsy in 2001, when I was 24. Luckily, my seizures are easily controlled by a drug called levetiracetam, also known as Keppra. Its side effects, according to the manufacturer’s Web site, include “psychotic symptoms, suicidal ideation, irritability, and aggressive behavior.”
I’ve been spared the worst of these. But irritability? Well, I once screamed at a man on the street who saw me carrying a heavy air conditioner and dared to suggest that it might be smarter to put the unit in my car.
But irritability is a vague condition. It’s not a specific malady such as a rash or vomiting, but a state of mind. It even appears in the Diagnostic and Statistical Manual of Mental Disorders.
I could blame a pharmaceutical for my anger-management failures. But before I took Keppra, I was an impatient child, a moody teenager and a testy young adult. You could say I’ve been irritable since birth.
I’m not sure if I’m more or less irritable than I was before Keppra. The older I get, the more stressed I get. Sure, I get steamed when my toddler throws broccoli to get my attention or when my dog goes after the mailman. How can I compare my state of mind today to that of a decade ago, when I didn’t have a daughter or a dog?
How much of my current irritability is Keppra, and how much is just me?
“There’s one end of the bell curve where it’s obvious,” says David Spencer, a professor of neurology at Oregon Health and Science University in Portland. “The behavior is way out of range.”
Spencer describes two of his patients who may have been driven to abnormal behavior by levetiracetam. One, a “mild-mannered” academic, collared a student who asked about a grade. Another started displaying psychotic behavior, left his family and moved to Mexico.
“Those are exceptions. The common one is ‘He’s a little snappier than he used to be,’ ” Spencer says. But it’s hard to parse the chemical and the psychological. “Was it just something that happened to him, or was it the drug?”
No one can say for sure.
“If you find somebody [who] can, I’d like to talk to them,” says Steve White, the scientific director of a program at the University of Utah that aims to develop anticonvulsant drugs for people who are prone to seizures. White points out that 30 percent of epilepsy patients are depressed and don’t necessarily need Keppra to be irritable.
“Seizures themselves are associated with neurochemical changes,” he says. As for the irritability displayed by people on levetiracetam, “it would be difficult for anyone to put their finger on it and say, ‘This is the real reason.’ ”
White has special authority in thinking about levetiracetam: After having a seizure related to a brain tumor, he started taking the drug.