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 delayed-release capsule formulation of valproic acid (VPA; Stavzor - Noven Therapeutics) for all of the indications for which divalproex sodium (Depakote, and others; Depakote ER) is approved: monotherapy and adjunctive therapy of complex partial seizures and simple and complex absence seizures, and adjunctive therapy in patients with multiple seizure types that include absence seizures; acute treatment of manic episodes associated with bipolar disorder; and prophylaxis of migraine headaches. In addition, valproate (valproic acid or divalproex sodium) is considered a...

Gabapentin (Neurontin - Parke-Davis), a cyclohexane acetic acid derivative, has been approved by the US Food and Drug Administration for use in addition to other antiepileptic drugs in patients with partial (focal) seizures with or without secondary generalization. Since this diagnostic category includes the largest number of patients with intractable epilepsy, new drugs with antiepileptic activity are generally tried first for this indication.

Felbamate (Felbatol - Wallace Laboratories), a phenyl dicarbamate structurally similar to meprobamate (Equanil, and others), was recently approved by the US Food and Drug Administration for use alone or with other drugs in adults with partial seizures with or without secondary generalization. It was also approved for use in addition to other drugs in children with the multiple types of seizures associated with the Lennox-Gastaut syndrome, a severe epileptic encephalopathy.

The FDA has approved nasal spray formulations of the benzodiazepines diazepam (Valtoco — Neurelis) and midazolam (Nayzilam — UCB) for acute treatment of intermittent episodes of frequent seizure activity (seizure clusters). Diazepam rectal gel (Diastat, Diastat AcuDial, and generics) has been used for this indication for many years.

Cannabis (marijuana) contains more than 60 pharmacologically active cannabinoids; delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) are the best known. THC is the main psychoactive constituent of cannabis. CBD, unlike THC, does not produce intoxication or euphoria.

Gabapentin (Neurontin - Pfizer), which has been available in the US since 1994, is approved by the FDA only for treatment of partial epilepsy and postherpetic neuralgia, but is widely used off-label for a number of other indications, especially neuropathic pain syndromes. According to one report, among Medicaid recipients in Florida receiving gabapentin, 71% of prescriptions were for chronic pain and 8% for seizures and neuralgia ("The Pink Sheet" February 2, 2004; 66:30).

The FDA has approved stiripentol (Diacomit – Biocodex) for treatment of seizures in patients ≥2 years old with Dravet syndrome who are also taking clobazam (Onfi). Stiripentol, which has been available in Europe, Canada, and Japan for many years, is the second drug to be approved in the US for this indication; cannabidiol oral solution (Epidiolex), a purified marijuana product, was the first.

The FDA recently announced changes in the labeling of ezogabine (Potiga – GSK/Valeant) to warn about the risks of retinal abnormalities, possible vision loss, and bluish skin discoloration, all of which could be permanent.1Ezogabine was approved in 2011 for adjunctive treatment of partial-onset seizures in adults.2 The FDA first warned about these risks in April 2013.3 At that time, skin discoloration had developed in 38 of an estimated 605 patients (6.3%) who had taken the drug (most for ≥2 years) in various studies. Retinal pigment abnormalities were found in 11 of 36 patients who had...

The FDA has approved ganaxolone (Ztalmy – Marinus) for oral treatment of seizures associated with cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder in patients ≥2 years old. It is the first drug to be approved in the US for this indication.