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5 things patients should know about generic anti-seizure medications

They are less expensive, but do they work as well? A Texas A&M researcher and registered pharmacist explains

Epilepsy is a chronic neurologic condition that affects about 50 million people worldwide, but there is currently no pharmaceutical cure for epilepsy. The hallmark symptom of epilepsy is repeated seizures, which can be treated with anti-seizure medications (ASMs). Though ASMs may not fully eliminate seizures, they frequently enable patients with epilepsy to lead relatively normal lives. However, brand name ASMs can be expensive, so providers have gradually been shifting from prescribing brand name drugs to generic medications.

Professor D. Samba Reddy, PhD, RPh, and fourth-year medical student Sarah Elmer, both of the Texas A&M University School of Medicine’s Department of Neuroscience and Experimental Therapeutics, put together a systematic review of the most current clinical research surrounding generic ASMs, because it’s more important than ever for patients with epilepsy to understand generic ASMs.

“I am grateful to Dr. Reddy and the Texas A&M School of Medicine for giving me the opportunity to research such an important topic,” Elmer said. “I am hopeful that our findings will contribute to improved patient safety by helping to prevent adverse outcomes associated with switching between brand name and generic anti-seizure medications.”

Based on their findings, here are five key things patients should know about generic ASMs.

Generic anti-seizure medications are bioequivalent to brand name medications.

A generic drug is one that is similar (or bioequivalent) to a brand name drug in dosage form, safety, strength, mode of administration, quality, performance characteristics and intended use, according to the United States Food and Drug Administration (FDA).

The FDA further defines bioequivalence as a lack of a significant difference between the brand name medication and generic alternative in the rate and extent to which the active ingredient becomes available. This is tested through a clinical pharmacokinetic study that ensures that both drugs are administered at the same site and dosage while controlling for other conditions.

There are dozens of different types of anti-seizure medications that all have different actions, targets and effects, so finding comparable substitutions can be a complex task for doctors. However, generic ASMs demonstrate bioequivalence to their brand name counterparts, meaning there are essentially no differences except for nuances like the name, color or shape.

Generic anti-seizure medications are significantly more affordable than brand name medications.

The major difference between generic ASMs and their brand name counterparts is their cost to patients.

For patients who have health insurance, this difference in cost is largely due to the tiered structure in which medications are classified by insurance companies. More expensive pharmaceuticals fall into a tier that raises patient costs, while generic medications and other replacements fall into a different tier that is more economical for the patient.

For economically disadvantaged people or those without health insurance, generic ASMs are far more financially accessible than brand name. While brand name pharmaceuticals must factor in discovery, clinical trials, production, marketing, storage, transport, personnel and other associated expenditures, generic medicines eliminate many of these costs, making the medicines more affordable for the patient.

Generic anti-seizure medications still need to be prescribed by a doctor.

Many people conflate the concept of generic drugs with over-the-counter medications, but because generic drugs are identical to brand-name seizure medications, these medications still require a prescription from a physician or other provider.

As mentioned before, identifying the best generic ASM for a patient is a complex task that considers many different criteria, and the decision can only be made by a licensed physician, physician assistant or advanced practice nurse. Arguably the most crucial factor for a doctor to consider when treating epilepsy is the generic ASM’s Narrow Therapeutic Index, also called a therapeutic window.

A narrow therapeutic window means that a slight difference in dosing or blood concentration of a medication can cause seizures or adverse reactions that may have potentially life-threatening effects. Because of this, doses of these drugs must be monitored closely and administered carefully.

Drugs classified as having narrow therapeutic windows are subject to stricter regulations for substitution of brand name with generic and allow only a narrow margin of pharmacokinetic difference between the generic and brand product. Although five ASMs are currently listed as having narrow therapeutic windows (carbamazepine, phenytoin, phenobarbital, ethosuximide, valproic acid) many experts, including Reddy, recommend that all ASMs be considered such, in the interest of patient safety.

Generic anti-seizure medications require patients to follow instructions very carefully.

Since dosage and blood concentrations are so critical in the therapeutic success of a medication, it is vital that patients follow every instruction that their provider gives them regarding their prescription. This includes when to take the medication, how often to take it and whether to take it with food or on an empty stomach.

If the treatment plan for epilepsy originally started with a brand name medication, and a patient is now being transitioned to a generic equivalent, it is still recommended to read all instructions and ask any clarifying questions, because the information may be different in the generic version. Sometimes changes—even small ones like the color of the pill—can cause patients to no longer adhere to the doctor’s instructions, but these medications are essential for managing epilepsy in the long term, and the only way to reap these benefits is by taking the medication as instructed.

Generic anti-seizure medications will only work if you give them a chance!

The mind influences our perceptions of our own health a lot more than we may realize, so it is important to keep an open mind when taking generic ASMs and evaluating their effects. Similar to how some people may think the brand name cereal is tastier than the store brand because of the familiarity of the packaging and advertising, both doctors and patients are prone to biases and external influences that make them feel that brand name medications are superior to generic equivalents.

Although this perception may seem harmless, studies have shown that when individuals—both patients and physicians alike—expect the generic medications to be inferior, they also assume that they have a reduced therapeutic effect. This is known as the “nocebo effect” and researchers explain that if a patient expects to have a negative experience after starting a new generic ASM, this results in the treatment having a more negative effect.

To combat this, patients and physicians need to have conversations about the generic ASM a patient is being prescribed so that there is an open line of communication to convey information, questions and concerns. This needs to be a continual process that starts before the patient starts taking the generic ASM, and should carry through as long as the patient is taking the medication.

Final things to keep in mind

Generic anti-seizure medications are a great alternative to their more expensive brand-name counterparts, and it’s worth asking your doctor about generic anti-seizure medications. These medications have shown varying degrees of success in patients, but those who have had the best experience, Reddy said, are the ones who use these medications under the close supervision of a physician or other provider and who speak to their pharmacist who can provide education, instructions and guidance on the treatment.

Media contact: Dee Dee Grays,, 979.436.0611

Sunitha Konatham

Communications Coordinator

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