Patients with frequent, severe or disabling migraine headaches may benefit from taking a drug to prevent the attacks. Beta-blockers traditionally have been the prophylactic treatment of choice, but in recent years some antiepileptic drugs such as valproate (Depakote, and others) and topiramate (Topamax) have also been used for this indication. Valproate was approved by the FDA for such use in 1996. Now topiramate has also been approved.

The FDA has approved a new extended-release capsule formulation of topiramate (Qudexy XR – Upsher Smith), which can be opened and sprinkled on food for patients who have difficulty swallowing tablets or capsules, for treatment of epilepsy. Qudexy XR was marketed as a branded drug in March 2014 and as a generic drug four months later. An earlier extended-release formulation (Trokendi XR) must be swallowed whole.Trokendi XR is approved for initial monotherapy in patients ≥10 years old with partial-onset seizures or primary generalized tonic-clonic seizures and for adjunctive therapy in...

The FDA has approved a once-daily extended-release (ER) formulation of the antiepileptic topiramate (Trokendi XR – Supernus) for initial monotherapy in patients ≥10 years old with partial onset seizures or primary generalized tonic-clonic seizures and for adjunctive therapy in patients ≥6 years old with partial onset seizures, primary generalized tonic-clonic seizures, or seizures associated with Lennox-Gastaut syndrome. Topiramate has been available for many years as an immediate-release (IR) formulation (Topamax, and generics) for the same indications in patients ≥2...

The FDA has approved injection of onabotulinumtoxinA (Botox – Allergan) for prevention of headaches in adult patients with chronic migraine (≥15 headache days/month for ≥3 months). It is the first drug approved for treatment of this indication. Botox is also FDA-approved for treatment of upper limb spasticity, axillary hyperhidrosis, cervical dystonia, blepharospasm and strabismus, and for cosmetic reduction of wrinkles.

Topiramate (Topamax - Ortho-McNeil) has been approved by the US Food and Drug Administration (FDA) for oral use as an adjunct to other drugs in adult patients with partial seizures. Since this diagnostic category includes the largest number of patients with refractory epilepsy, new drugs with antiepileptic activity are usually tried first for this indication. Topiramate (toe pyre' a mate) is a structurally unique agent chemically related to the D-enantiomer of fructose.

Rufinamide (Banzel - Eisai), a triazole derivative structurally unrelated to other marketed antiepileptic drugs (AEDs), has been approved by the FDA for treatment of seizures associated with Lennox-Gastaut syndrome (LGS) in patients ≥4 years old.

Zonisamide (Zonegran - Elan Pharma), a sulfonamide chemically unrelated to other antiepileptic drugs, has been approved by the FDA for adjunctive use in adults with partial seizures. Zonisamide has been available in Japan for more than 10 years.

Clobazam (Onfi – Lundbeck), an oral benzodiazepine, has been approved by the FDA for adjunctive treatment of seizures associated with Lennox-Gastaut syndrome (LGS) in patients ≥2 years old. It has been available in Canada (Frisium) and other countries for years for treatment of anxiety and many types of epilepsy.

The equivalence of generic drugs to their brand-name precursors continues to be controversial. The last Medical Letter review of this subject (2002) concluded that well-documented therapeutic inequivalence between brand-name and FDA-approved generic drugs had not been reported. Is that still true? New data have become available for some drugs.

The FDA has approved ezogabine (ee-ZOE-ga-been; Potiga – GSK/Valeant) for oral adjunctive treatment of partial-onset seizures in adults. Ezogabine is available in Europe as retigabine (Trobalt).