...

Lyme disease in the US is caused by the spirochete Borrelia burgdorferi, which is transmitted to humans by Ixodes scapularis (blacklegged [deer] tick) and I. pacificus (western blacklegged tick). Most cases of Lyme disease occur in late spring and early summer in northeastern and mid-Atlantic states, the upper Midwest, and in northern California. B. mayonii, which is also transmitted by I. scapularis, has been shown to cause a similar illness in the upper Midwest.

Cognitive behavioral therapy for insomnia (CBT-I) is recommended for initial treatment of chronic insomnia. CBT-I includes stimulus control, sleep education and hygiene, sleep restriction, relaxation training, and cognitive therapy. When CBT-I alone is not effective, pharmacologic treatment should be added.

Annual vaccination in the US against influenza A and B viruses is recommended for everyone ≥6 months old without a contraindication. Influenza vaccines available in the US for the 2024-2025 season are listed in Table 2.

Several Medical Letter readers have asked about the meaning of non-inferiority trials. A non-inferiority trial is a comparison with an active control to determine whether the difference in response between the new drug and the active control is small enough (less than some pre-specified margin) to demonstrate that the new treatment is not less effective (or is only slightly less effective) than the control in achieving the primary outcome.1,2 Non-inferiority trials are appropriate when a proven effective treatment already exists and assigning some patients to a placebo group would be unethical...

The US Advisory Committee on Immunization Practices (ACIP) now recommends routine immunization with 13-valent pneumococcal conjugate vaccine (PCV13; Prevnar 13), in addition to the 23-valent pneumococcal polysaccharide vaccine (PPSV23; Pneumovax 23), for all adults ≥65 years old.1An unpublished, randomized, double-blind trial (CAPiTA) in about 85,000 adults ≥65 years old found that vaccination with PCV13 reduced first episodes of vaccine-type community-acquired pneumonia and invasive pneumococcal disease by 46% and 75%, respectively, compared to placebo.2Adults ≥65 years old who...

Our December 11, 2023 article on Drugs for Depression included a single sentence on the safety of bupropion use during pregnancy: "The safety of bupropion during pregnancy has not been established; data from a bupropion pregnancy registry suggested a possible increase in cardiac malformations." A reader asked us to provide more information.

The FDA has approved the proton pump inhibitor (PPI) esomeprazole strontium for use in adults for the same indications as esomeprazole magnesium (Nexium): treatment of gastroesophageal reflux disease (GERD), prevention of NSAID-induced gastric ulcers, eradication of Helicobacter pylori, and treatment of pathological hypersecretory conditions. It was first marketed in December 2013 as a branded drug (Esomeprazole Strontium) and a month later as a generic drug.Strontium is incorporated into bone. It is not recommended for use in children or during pregnancy because of the absence of safety data...

Wild poliovirus has circulated during the previous 12 months in Cameroon, Equatorial Guinea, Ethiopia, Iraq, Israel (also the West Bank and Gaza), Somalia, and Syria, as well as in those countries where polio is still endemic (Afghanistan, Nigeria, and Pakistan). The World Health Organization (WHO) has declared a public health emergency related to the possible spread of polio from affected countries. In response, the Centers for Disease Control and Prevention (CDC) has issued interim guidance for US residents planning travel to and from these countries.Vaccine Recommendations – All travelers...

Homeopathic drugs characteristically consist of very large dilutions of "proven" substances. Serial dilutions of 1:10 are designated by the Roman numeral X. ColciGel (Gensco), a prescription homeopathic gel containing a 10,000-fold dilution of colchicine (colchicinum 4X), is now being marketed for topical treatment and prophylaxis of gout.