A reader has questioned why the label for the COX-2 selective NSAID celecoxib (Celebrex, and generics), which contains a sulfonamide moiety, states that it is contraindicated for use in patients with an allergy to sulfonamides, while the labels of some other sulfonamide drugs recommend either caution or no precautions at all. The concept of cross-reactivity among sulfonamide drugs, particularly between antibacterial and nonantibacterial sulfonamides, has been controversial for many years.

Pharmacologic management of opioid withdrawal symptoms can reduce the intensity of drug craving and improve treatment retention in patients with opioid use disorder who will receive maintenance treatment. Withdrawal management without subsequent maintenance treatment is associated with high rates of relapse, overdose death, and HIV and/or hepatitis C virus infection. Several guidelines on management of opioid withdrawal are available. Maintenance treatment of opioid use disorder was reviewed in a previous issue.

Dorzolamide hydrochloride (Trusopt - Merck), a thienothio-pyran-2-sulfonamide carbonic anhydrase inhibitor, was recently approved by the US Food and Drug Administration in a 2% ophthalmic solution for treatment of elevated intraocular pressure in patients with ocular hypertension or open-angle glaucoma.

The FDA has approved daclatasvir (Daklinza – BMS), an oral direct-acting antiviral drug, for use with sofosbuvir (Sovaldi) for treatment of chronic hepatitis C virus (HCV) genotype 3 infection. Daclatasvir is the first drug approved for this indication that does not require the addition of interferon or ribavirin. It is approved in Japan and Europe in combination with other drugs for treatment of HCV genotypes 1-4.

On December 22, 2021, the FDA issued an Emergency Use Authorization (EUA) for the investigational antiviral drug nirmatrelvir copackaged with the HIV-1 protease inhibitor ritonavir (Paxlovid – Pfizer) for oral treatment of mild to moderate COVID-19 in outpatients ≥12 years old who weigh at least 40 kg and are at high risk of progressing to severe disease, including hospitalization or death. Paxlovid was the first oral antiviral drug to be authorized in the US for treatment of COVID-19; Merck's oral antiviral drug molnupiravir was granted an EUA for treatment of COVID-19 on...

Alprazolam, a short-acting benzodiazepine, is one of the most widely prescribed drugs in the US. It is approved by the FDA for treatment of anxiety and panic disorder. An extended-release formulation, Xanax XR, which can be taken once a day, recently became available for panic disorder.

Paliperidone (Invega - Janssen) has been approved by the FDA in an extended-release formulation for treatment of schizophrenia. It is the primary active metabolite of the second-generation antipsychotic risperidone (Risperdal - Janssen), which is scheduled to lose its patent exclusivity in December 2007.

Finasteride (Proscar - Merck) has now been approved by the US Food and Drug Administration (FDA) for oral treatment of benign prostatic hyperplasia. A 4-aza-steroid, the drug is a specific inhibitor of steroid 5 -reductase, the enzyme that catalyzes conversion of testosterone to dihydrotestosterone. Dihydrotestosterone is required for development and maintenance of prostatic hypertrophy (JS Tenover, Endocrinol Metab Clin North Am, 20:893, 1991).

Minoxidil 2% topical solution (Rogaine - Upjohn) has been available in the USA since 1988 for treatment of androgenetic alopecia (Medical Letter, 29:87, 1987). Although available only by prescription, it is advertised on television to the general public.

Modafinil (Provigil), a benzhydryl sulfinylacetamide non-amphetamine stimulant that has been used in Europe since 1995, has now been approved by the FDA for treatment of excessive daytime sleepiness associated with narcolepsy.