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.

Anticonvulsants are now widely used for treatment of psychiatric illnesses, particularly bipolar disorder. Lithium is the standard drug for treatment of bipolar disorder, but it can cause severe toxicity, serum concentrations must be monitored, and it is not effective in some patients.

Bipolar disorder is characterized by episodes of mania, hypomania, and depression. Recurrences of manic or (more frequently) depressive symptoms are common. About 15-20% of patients with bipolar disorder die by suicide.

Tiagaine (Gabitril - Abbot), a gamma-aminobutyric acid (GABA) uptake inhibitor, has been approved by the FDA for oral use as an adjunct to other drugs for treatment of partial seizures in patients more than 12 years old. Since most adult patients with resistant epilepsy have partial seizures, new antiepileptic drugs are usually tried first for this indictation.

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.

Carnitine is a naturally occurring amino acid derivative essential for transport of long-chain fatty acids into mitochondria. It is advertised on the Internet as a dietary supplement that can promote weight loss, increase energy, enhance athletic performance and slow aging. Levocarnitine (Carnitor - Sigma-Tau) has been FDA approved for oral and parenteral treatment of primary carnitine deficiency since 1986. Products containing levocarnitine and its synthetic derivative acetyl-L-carnitine are available as dietary supplements in the US.

Oxcarbazepine, which is chemically similar to carbamazepine, and levetiracetam, a pyrrolidine acetamide chemically unrelated to other antiepileptic drugs, are the sixth and seventh drugs approved by the US Food and Drug Administration in the last five years for oral use in partial seizures.

The FDA has approved erenumab-aooe (Aimovig – Amgen/Novartis), a once-monthly, subcutaneously-injected, monoclonal antibody against the calcitonin gene-related peptide receptor, for preventive treatment of migraine in adults. It is the first drug in its class to be approved by the FDA.

An oral nonopioid analgesic is often sufficient for acute treatment of mild to moderate migraine pain without severe nausea or vomiting. A triptan is the drug of choice for treatment of moderate to severe migraine in most patients without vascular disease. Treatment of pain when it is still mild to moderate in intensity improves headache response and reduces the risk of recurrence.

The FDA has approved two subcutaneously injected calcitonin gene-related peptide (CGRP) antagonists, fremanezumab-vfrm (Ajovy – Teva) and galcanezumab-gnlm (Emgality – Lilly), for migraine prevention in adults. Fremanezumab and galcanezumab are the second and third subcutaneously injected monoclonal antibodies that target the CGRP pathway to be approved by the FDA for this indication; erenumab-aooe (Aimovig), which targets the CGRP receptor, was the first.