The FDA has approved Relyvrio (Amylyx), a fixed-dose combination of sodium phenylbutyrate and taurursodiol, for treatment of amyotrophic lateral sclerosis (ALS). Sodium phenylbutyrate (Buphenyl, and others) has been available by prescription for years for treatment of urea cycle disorders. Taurursodiol (tauroursodeoxycholic acid), a derivative of ursodiol, is an over-the-counter bile acid supplement claimed to have neuroprotective benefits. Relyvrio is the third drug to be approved in the US for treatment of ALS; riluzole (Rilutek, and others) and edaravone (Radicava, Radicava...

About 2.5 million persons in the US had hepatitis C between 2017 and 2020. Guidelines from the American Association for the Study of Liver Diseases (AASLD) and the Infectious Diseases Society of America (IDSA) on management of hepatitis C virus (HCV) infection were updated in 2023.

Treatment of community-acquired pneumonia (CAP) is usually empiric, with selected antibiotic regimens directed against some of the most common causative pathogens. Recommended empiric regimens are listed in Table 2; recommended antibiotic dosages for treatment of CAP are listed in Tables 3 and 4. Joint guidelines for treatment of CAP by the American Thoracic Society and the Infectious Diseases Society of America (ATS/IDSA) were updated in 2019.

Onychomycosis is caused most commonly by Trichophyton rubrum or T. mentagrophytes. About 10% of all persons worldwide and 40% of those ≥60 years old are believed to have the disease. Risk factors include older age, diabetes, poor peripheral circulation, smoking, HIV infection, psoriasis, and immunosuppression. Left untreated, onychomycosis can cause nail plate destruction, ingrown nails, and (particularly in patients with diabetes) secondary infections. Guidelines on treatment of onychomycosis have been published.

Primary hypothyroidism is usually the result of Hashimoto's (autoimmune) thyroiditis, thyroidectomy, or radioactive iodine therapy. Treatment of hypothyroidism with replacement doses of thyroid hormone is usually lifelong. Levothyroxine (LT4; synthetic thyroxine; Synthroid, and others) is the drug of choice.1

Most respiratory tract infections are caused by viruses. Bacterial respiratory tract infections are usually treated empirically with antibiotic therapy that targets the most probable causative pathogens. Recommended antibiotic regimens for outpatient treatment of some common respiratory tract infections are listed in Table 1 for adults and Table 2 for children.

Influenza is generally a self-limited illness, but pneumonia, respiratory failure, and death can occur, especially in persons at increased risk for influenza complications (see Table 1). Updated information on influenza activity and antiviral resistance is available from the CDC at cdc.gov/flu.

Rheumatoid arthritis (RA) is prevalent in 0.5% of adults in the US; it is about 2.5 times more common in women than in men. Guidelines for treatment of RA from the American College of Rheumatology were recently updated. The goal of treatment is to minimize disease activity and prevent irreversible joint damage.

This article includes recommendations for management of most sexually transmitted infections (STIs) other than HIV and viral hepatitis. Some of the indications and dosages recommended here have not been approved by the FDA (see Table 1).

Pharmacologic treatment is recommended for postmenopausal women who have bone density T-scores (standard deviations from normal mean values in the spine, femoral neck, total hip, or distal radius) of -2.5 or below, T-scores between -1.0 and -2.5 with a history of fragility (low-trauma) fracture of the hip or spine, or T-scores between -1.0 and -2.5 with a FRAX 10-year probability of ≥3% for hip fracture or ≥20% for major osteoporotic fracture.