The FDA has approved tenofovir alafenamide (Vemlidy – Gilead) for treatment of chronic hepatitis B virus (HBV) infection in adults with compensated liver disease. It is the first single-drug product containing tenofovir alafenamide (TAF), a prodrug of the nucleotide reverse transcriptase inhibitor tenofovir, to become available; several combination products containing TAF are approved for treatment of HIV-1 infection. Tenofovir disoproxil fumarate (TDF; Viread – Gilead), another tenofovir prodrug, has been used for many years for treatment of chronic HBV infection; a generic...

Every pharmaceutical drug is a dose-dependent poison. This article describes the clinical presentation and treatment of some dangerous overdoses commonly reported in adults.

Irritable bowel syndrome (IBS) is a common disorder characterized by recurrent abdominal pain and altered bowel habits, often accompanied by bloating. IBS is classified by its predominant bowel symptom: constipation (IBS-C), diarrhea (IBS-D), mixed type (IBS-M), or unclassified (IBS-U). Since the exact cause of IBS is unknown, the goal of treatment is symptom control. Some over-the-counter (OTC) products and prescription drugs for IBS are listed in Tables 1-4. The safety of these drugs during pregnancy and lactation is described in Table 5 (online only).

Antimicrobial prophylaxis can decrease the incidence of postoperative surgical site infection after some procedures. Since the last Medical Letter article on this subject, consensus guidelines have been published. Recommendations for prophylaxis in specific surgical procedures are listed in Table 1.

The drugs of choice for treatment of viral infections (other than HIV) and their dosages are listed in Tables 1-6 on the pages that follow. Some of the indications and dosages recommended here have not been approved by the FDA. Vaccines used for the prevention of viral infections are discussed elsewhere.