The Medical Letter article on Detrol LA and Ditropan XL (vol.43, page 28, April 2, 2001) stated that these drugs should not be used in patients with glaucoma. That statement is misleading because anticholinergic or antimuscarinic drugs present a risk only to patients with untreated angle-closure (also called narrow-angle) glaucoma, which accounts for 10% of glaucomas in the USA. These drugs have no effect on the more common open-angle glaucoma, or on angle-closure glaucoma that has been treated by laser iridectomy.

Correction: In the table on Drugs of Treatment for Viral Infections (volume 44, page 10, February 4, 2002), the dosage of valacyclovir for treatment of recurrence of genital herpes should be 500 mg PO b.i.d. (not 1 x/day) x 3 days, and the cost should be $21.70.

View Table: Mechanisms of Drug Interactions

The FDA recently announced labeling changes for the combination antiviral products Viekira Pak (ombitasvir/paritaprevir/ritonavir with dasabuvir)1 and Technivie (ombitasvir/paritaprevir/ritonavir)2 warning of a risk of serious, potentially fatal liver injury.3 Viekira Pak, approved in December 2014 for treatment of hepatitis C virus (HCV) genotype 1 infection, including patients with compensated cirrhosis, and Technivie, approved in July 2015 for treatment of HCV genotype 4 infection without cirrhosis, have been identified as "possible" or "probable" causes in 26 postmarketing cases of hepatic...

Azelaic acid, a naturally occurring heptanedicarboxylic acid, has been marketed in the USA as a 20% cream (Azelex - Allergan) for treatment of acne. The drug has been available in Europe for several years.

Three extended-release injectable formulations of second-generation antipsychotic drugs — two of risperidone (Rykindo, Uzedy) and one of aripiprazole (Abilify Asimtufii) — have been approved by the FDA for treatment of schizophrenia in adults. Rykindo and Abilify Asimtufii are also approved for maintenance treatment of bipolar I disorder in adults. Other extended-release injectable formulations of risperidone and aripiprazole have been available in the US for years (see Table 1).

The FDA has approved Acuvue Theravision with Ketotifen (Johnson & Johnson Vision Care), a daily-wear, disposable, vision-correcting soft contact lens that releases the H₁-antihistamine ketotifen, for prevention of ocular itch due to allergic conjunctivitis in contact lens users. This is the first approval for a drug-eluting contact lens. Ketotifen eye drops (Alaway, Zaditor, and others) are available over the counter.

The FDA has approved siponimod (Mayzent – Novartis), a sphingosine 1-phosphate (S1P) receptor modulator, for oral treatment of adults with relapsing forms of multiple sclerosis (MS), including clinically isolated syndrome (initial neurological episode), relapsing-remitting disease, and active secondary progressive MS (SPMS). Siponimod is the second S1P receptor modulator to be approved in the US; fingolimod (Gilenya), which is approved for oral treatment of relapsing forms of MS in patients ≥10 years old, was the first. The purine antimetabolite cladribine (Mavenclad) was also...

A drug that combines the neutral sulfate salts of dextroamphetamine and racemic amphetamine with the dextro isomer of amphetamine saccharate and d,l amphetamine aspartate (Adderall - Richwood Pharmaceutical) has recently been promoted for treatment of children with Attention-Deficit/Hyperactivity Disorder (ADHD). This same mixture of amphetamine salts was previously marketed as Obetrol for treatment of obesity.

Methicillin-resistant Staphylococcus aureus (MRSA), which was traditionally a nosocomially-acquired organism but now frequently occurs in the absence of healthcare exposure, is the predominant cause of suppurative skin and soft-tissue infections in many parts of the US. Community-associated MRSA usually causes furunculosis, purulent cellulitis, and abscesses, but necrotizing fasciitis, necrotizing pneumonia, and sepsis can also occur.