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.

Zanamivir, a neuraminidase inhibitor taken by inhalation, has been approved by the FDA for treatment of influenza. Oseltamivir phosphate, an oral neuraminidase inhibitor, will probably be approved soon.

Amlodipine (am loe' di peen) besylate (Norvasc - Pfizer), a dihydropyridine calcium-channel blocker, has been approved by the US Food and Drug Administration for once-daily oral treatment of hypertension, chronic stable angina, and vasospastic (Prinzmetal's) angina.

The FDA has approved a once-daily, extended-release oral suspension of methylphenidate (Quillivant XR – Pfizer) for treatment of attention-deficit/hyperactivity disorder (ADHD). It is the first liquid formulation of the drug to be marketed for once-daily use. A short-acting oral solution (Methylin, and generics) has been available since 2003.

The FDA has approved pembrolizumab (Keytruda – Merck), a human programmed death receptor-1 (PD-1) blocking antibody, for treatment of unresectable or metastatic melanoma that has progressed following treatment with ipilimumab (Yervoy) and, if the patient is BRAF V600 mutation positive, a BRAF inhibitor. It is the fi rst PD-1 inhibitor to be marketed in the US. Nivolumab, another PD-1 inhibitor, is available in Japan. Pembrolizumab was previously known as lambrolizumab.

Low-dose aspirin is widely used as an antiplatelet drug to reduce the risk of cardiovascular disease (Medical Letter 2000; 42:18). Recent reports suggest that the nonsteroidal anti-inflammatory drug (NSAID) ibuprofen (Motrin, and others) may decrease the efficacy of aspirin for this indication. The manufacturer of Tylenol is capitalizing on these reports by advertising that aspirin-taking patients who need pain relief should use acetaminophen instead of ibuprofen.

The FDA has approved the immune checkpoint inhibitor pembrolizumab (Keytruda – Merck), a programmed death receptor-1 (PD-1) inhibitor, for first-line treatment of patients with metastatic non-small cell lung cancer (NSCLC) that highly expresses programmed death-ligand 1 (PD-L1) and has no epidermal growth factor receptor (EGFR) mutations or anaplastic lymphoma kinase (ALK) translocations. About 25% of patients with advanced NSCLC have tumors with high levels of PD-L1 expression (PD-L1 expressed on ≥50% of tumor cells). Pembrolizumab was approved earlier for treatment...

Echinacea, a plant also called purple coneflower, is widely used as a dietary supplement for prevention and treatment of colds.

The FDA has approved Entadfi (Veru), a fixed-dose combination of the 5α-reductase inhibitor finasteride and the phosphodiesterase type 5 (PDE5) inhibitor tadalafil, for initial treatment of benign prostatic hyperplasia (BPH) in men with an enlarged prostate; use of the drug is limited to 26 weeks. Entadfi is the first 5α-reductase inhibitor/PDE5 inhibitor combination to become available in the US. Finasteride (Proscar, and generics) and tadalafil (Cialis, and generics) are also available separately.

Omeprazole (Losec - Merck), a new drug that suppresses gastric acid secretion, has been approved by the US Food and Drug Administration for short-term (four to eight weeks) treatment of severe or refractory gastroesophageal reflux and for long-term treatment of pathological hypersecretory conditions such as Zollinger-Ellison syndrome, multiple endocrine adenomas, and systemic mastocytosis. Although widely used abroad for treatment of peptic ulcers, it has not been approved for that indication in the USA.