Roflumilast (Daliresp – Forest), an oral phosphodiesterase 4 (PDE4) inhibitor, was approved by the FDA to reduce the risk of exacerbations in adult patients with severe chronic obstructive pulmonary disease (COPD) associated with chronic bronchitis and a history of exacerbations.

View Table: Mechanisms of Drug Interactions

Terfenadine (Seldane - Marion Merrell Dow) and astemizole (Hismanal - Janssen) are nonsedating antihistamines widely used to treat symptoms of allergic rhinitis (Medical Letter, 27:65, 1985; 31:43, 1989). Both are available without a prescription in Canada, and the US Food and Drug Administration is apparently considering terfenadine for over-the-counter availability in the USA.

The FDA has approved an inhaled fixed-dose combination (Breo Ellipta – GSK/Theravance) of the corticosteroid fluticasone furoate and the long-acting beta₂-adrenergic agonist (LABA) vilanterol trifenatate for once-daily treatment of chronic obstructive pulmonary disease (COPD).

View the Comparison Table: Drugs for Alzheimer's Disease

The FDA has approved Diclegis (Duchesnay), a fixed-dose, delayed-release combination of the H1-antihistamine doxylamine and the vitamin B6 analog pyridoxine, for treatment of nausea and vomiting of pregnancy in women who do not respond to conservative management. It is only available by prescription. Doxylamine and pyridoxine, both currently available over the counter, were previously available by prescription in a fixed-dose combination (Bendectin) for morning sickness. Bendectin was voluntarily withdrawn in the US in 1983 because of claims of teratogenicity that have since been...

The FDA has approved indacaterol (in´´ da ka´ ter ol; Arcapta Neohaler – Novartis), an inhaled long-acting beta₂-agonist, for once-daily maintenance treatment of airflow obstruction in patients with chronic obstructive pulmonary disease (COPD). Indacaterol is not approved for treatment of exacerbations of COPD or for treatment of asthma. It has been available in Europe as Onbrez Breezhaler since 2009.

The FDA has approved Cobenfy (BMS), an oral fixed-dose combination of the muscarinic agonist xanomeline and the peripheral muscarinic antagonist trospium chloride, for treatment of schizophrenia in adults. It is the first antipsychotic drug to be approved in the US for treatment of schizophrenia that does not block dopamine receptors. This is the first approval for xanomeline; trospium has been available for many years for treatment of overactive bladder.

The FDA has approved Zunveyl (Alpha Cognition), a delayed-release formulation of the prodrug benzgalantamine, for treatment of mild to moderate dementia of Alzheimer's disease (AD). Immediate- and extended-release formulations of the acetylcholinesterase inhibitor galantamine have been available in the US for years for treatment of AD.

Xerostomia, dry mouth due to decreased or absent saliva, is a common problem, particularly among elderly patients. Decreased salivary flow can be due to many different conditions, including drug therapy, Sj gren's syndrome (keratoconjunctivitis sicca) or radiation of the salivary glands.