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...

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.

Bedaquiline (bed ak' wi leen; Sirturo – Janssen), a diarylquinoline antimycobacterial, has been given accelerated approval by the FDA as an orphan drug for use in addition to other drugs for treatment of adults with multidrug-resistant pulmonary tuberculosis (MDR-TB). It is the first drug approved specifically to treat MDR-TB.

In 2011, the FDA asked the manufacturers of the selective serotonin reuptake inhibitor (SSRI) citalopram (Celexa, and generics) to lower the maximum daily dosage of the drug because of a dose-related increase in the QT interval. Since then, some of our readers have asked whether escitalopram (Lexapro, and generics), the active enantiomer of citalopram, could have the same effect.

The FDA has required the manufacturer of the secondgeneration antipsychotic quetiapine (Seroquel) to add a warning to the labeling saying that use of the drug should be avoided in combination with other drugs that prolong the electrocardiographic QTc interval (Table 1). The warning is based only on postmarketing reports of QT-interval prolongation in patients who overdosed on the drug, had concomitant illness, or were taking other drugs known to cause electrolyte imbalances or increase the QT interval. QT prolongation can lead to torsades de pointes, a potentially fatal cardiac...

Zanamivir, a neuraminidase inhibitor taken by inhalation, has been approved by the FDA for treatment of influenza. Oseltamivir phosphate, an oral neuraminidase inhibitor, will probably be approved soon.

The FDA recently issued a Drug Safety Communication saying that it had asked the manufacturer of ponatinib (Iclusig – Ariad) to suspend marketing and sales of the drug because of the risk of life-threatening blood clots and severe narrowing of blood vessels.1 Ponatinib is a tyrosine kinase inhibitor that was granted accelerated approval by the FDA in December 2012 for treatment of chronic-, accelerated, or blast-phase chronic myeloid leukemia (CML) and Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) resistant to (or the patients were intolerant to) prior tyrosine...

The FDA recently announced changes in the labeling of the hepatitis C drugs Sovaldi (sofosbuvir) and Harvoni (sofosbuvir/ledipasvir) to warn about a risk of serious and potentially fatal bradycardia when either drug is taken with the antiarrhythmic drug amiodarone (Cordarone, and others).1 Symptomatic bradycardia was reported following initiation of treatment with Harvoni or with Sovaldi plus simeprevir (Olysio) or the investigational antiviral drug daclatasvir in 9 patients already taking amiodarone; it occurred within 24 hours of starting hepatitis C therapy in 6 patients and within 2-12...

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.

Clozapine (Clozaril - Sandoz), an antipsychotic drug, was first marketed in the USA three years ago (Medical Letter, 32:3, 1990). Because of its hematological toxicity, the US Food and Drug Administration approved the drug only for patients with schizophrenia who cannot tolerate or do not respond to standard antipsychotic drugs.