Changes caused by one drug in the absorption, distribution, metabolism or excretion of another may lead to a pharmacokinetic adverse drug interaction (DN Juurlink et al, JAMA 2003; 289:1652). Additive drug interactions, such as vasodilation caused by both sildenafil (Viagra) and nitrates, can also have adverse effects.

Acne is common among adolescents and adults. Guidelines for treatment of acne were last published by the American Academy of Dermatology in 2016.

Adapalene (Differin - Galderma), a synthetic retinoid analog, has been marketed in the USA in a 0.1% gel formulation for topical treatment of acne vulgaris.

The FDA has approved another fixed combination of the antibiotic clindamycin phosphate and the oxidizing agent benzoyl peroxide (Onexton Gel 1.2%/3.75% – Valeant) for topical treatment of acne in patients ≥12 years old. Topical products containing the same drugs have been available for many years. Onexton Gel contains a new strength of benzoyl peroxide.

The FDA has approved azithromycin 1% ophthalmic solution (AzaSite - Inspire) for treatment of bacterial conjunctivitis in patients > 1 year old. It is formulated, according to the manufacturer, in a controlled-release delivery system that keeps the drug in the eye for several hours.

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).

Sparfloxacin (Zagam - Rh ne-Poulenc Rorer) and levofloxacin (Levaquin - Ortho-McNeil) are the newest fluoroquinolone antimicrobials to be approved by the US Food and Drug Administration. Sparfloxacin in a once-daily oral preparation is being marketed for treatment of community-acquired pneumonia and acute bacterial exacerbations of chronic bronchitis. Levofloxacin, which is the active stereoisomer of ofloxacin (Floxin), is available for either oral or parenteral use; it is approved for oncedaily treatment of community-acquired pneumonia, acute exacerbations of chronic bronchitis,...

Fexofenadine (fex oh fen' a deen) hydrochloride (Allegra - Hoechst Marion Roussel) has been approved by the US Food and Drug Administration for treatment of seasonal allergic rhinitis. An active metabolite of terfenadine, fexofenadine is being heavily advertised as "nonsedating...without 'black box' warnings."

A high-intensity, narrow-band blue light (ClearLight -Lumenis) approved by the FDA for treatment of moderate inflammatory acne vulgaris has been featured in some stories in fashion magazines. This review describes the etiology and treatment of acne, as well as the mechanism of action, clinical studies, adverse effects, dosage and cost of the drug.