tool name

Monday, Jul. 13, 2009

Danger in drug-switching

Changing to generic drugs can mean trouble for epileptics

Charlotte Gentry didn't realize that her epilepsy prescriptions had been changed from name brand to generic until after she had seizures that sent her to the emergency room.

Gentry, a diagnostic radiological technologist at Lexington's Veterans Administration Hospital, had been ordering her epilepsy medicine from a pharmacy that provided months of medicine at a time. She had had epilepsy for six years — after contracting viral meningitis — and had been on a variety of drugs before hitting on a combination that worked for her.

"I'm a very compliant patient," she said. "I do everything I can to control my seizures."

But she didn't notice when her Keppra and Triliptial were switched to generic formulations.

Four days later, she had four seizures in one night.

Most people have had prescriptions changed from name-brand to generic without incident: By the end of 2009, two-thirds of all prescriptions will be generic, according to a study by the health information company Wolters Kluwer.

And although many people think a generic prescription is just a cheaper version of the real thing, that's not exactly how it works. A company making a generic drug must show that its version of a drug is 80 percent to 125 percent "bioequivalent" to the original brand-name drug.

In many cases, that range won't matter. If, say, your brand-name sleep medicine Ambien becomes a generic zolpidem, you might notice no difference.

But Gentry and Lexington neurologist Warren Chumley of Associates in Neurology argue that, for epilepsy patients, subtle changes between drugs can make the difference between controlling seizures and starting the seizure cycle all over again.

Debbie McGrath, executive director of the Epilepsy Foundation of Kentuckiana, is planning a drive to make Kentucky legislators aware of the need to protect epilepsy patients from unannounced medicine switching.

At the least, McGrath says, pharmacists should be required to notify both the patient and the physician that a switch is going to be made. That way, the patient and doctor can decide together whether to work with the patient's insurance company to keep the person on the name-brand drug or examine the potency of a suggested generic.

States have broad authority to set their own boundaries for generic medicines. Tennessee and Hawaii, for example, require practitioner and patient consent for the substitution of any epilepsy drug.

At the least, Chumley suggests, a patient whose medicine is being switched deserves the opportunity to talk to his or her physician so the doctor can figure out how the alternative medicine works for the patient and how much risk of "breakthrough seizures" might be involved. With epileptics, the addition of something as seemingly uncomplicated as an antibiotic can change the level of anticonvulsants in a patient's bloodstream.

A short-term goal, Chumley said, would be simply to require that epilepsy patients receive branded medication. Over the long term, he said, there's so much variation in what patients receive in their generic drugs because there are so many generic drug manufacturers. If doctors prescribing for epilepsy patients knew they were working with, say, only three or four companies, that would reduce the margin of error.

The national Epilepsy Foundation condemns medicine-switching, which can include switching between different manufacturers' versions of the same generic drug, from a generic to a brand-name drug, or a brand-name drug to a generic. It says that the savings generated by "unsupervised switching" don't take into account the damage done to, and by, epilepsy patients who have additional seizures and then have auto accidents, miss work or require additional medical care.

The journal Neurology found that 21 of 26 patients studied had lower levels of epilepsy drugs in their systems when they had "breakthrough seizures" while on generic medicine.