Montelukast (Singulair - Merck) is an oral cysteinyl leukotriene D₄ receptor antagonist originally marketed for treatment of asthma. It was approved by the FDA in 2003 for treatment of seasonal allergic rhinitis and recently for use in perennial allergic rhinitis in adults and children ≥ 6 months old. Intranasal corticosteroids have generally been considered the most effective drugs available for prevention and treatment of allergic rhinitis.

A highly concentrated omega-3 polyunsaturated fatty acid (PUFA) preparation (Omacor - Reliant) has been approved by the FDA as an adjunct to diet for treatment of very high plasma triglyceride concentrations (>=500 mg/dL). Omacor is a combination of the ethyl esters of icosapentaenoic (EPA) and docosahexaenoic (DHA) acids. It is the first drug derived from omega-3 PUFAs to be sold by prescription.

Zolpidem (Ambien - Sanofi-Aventis), a nonbenzodiazepine benzodiazepine receptor agonist, is the most frequently prescribed hypnotic in the US. As its patent approaches expiration, its manufacturer has received FDA approval to market an extended-release formulation of the drug, Ambien CR. The pharmacological rationale for doing so is that short-acting hypnotics like zolpidem are more effective at inducing sleep than they are at maintaining it.

The FDA has approved marketing of the corticosteroid mometasone furoate in an orally inhaled dry powder formulation (Asmanex Twisthaler - Schering-Plough) for maintenance treatment of asthma in patients at least 12 years old. Mometasone is also available as a mid-potency topical corticosteroid cream (Elocon) and as an intranasal spray (Nasonex) for treatment of allergic rhinitis.

A fixed-dose combination of oxycodone 5 mg and ibuprofen 400 mg (Combunox - Forest Laboratories) is now available and is being heavily advertised for short-term treatment of moderate to severe acute pain.

Gamma hydroxybutyrate (GHB), a central-nervous-system depressant notorious for its use in "date rape", was approved by the FDA in 2002 as sodium oxybate (Xyrem - Jazz Pharmaceuticals) for oral treatment of cataplexy in patients with narcolepsy. Now it has also been approved for treatment of excessive daytime sleepiness (EDS) in these patients. Xyrem is a Schedule III controlled substance.

The FDA has approved a new spray formulation of the super-high-potency corticosteroid clobetasol propionate 0.05% (Clobex - Galderma) for treatment of moderate to severe plaque psoriasis in adults. Clobetasol propionate is also available as a cream, ointment, gel, solution, foam, lotion and shampoo.

Insulin glulisine (Apidra - Sanofi Aventis) is the third rapid-acting insulin analog to be marketed in the US, following insulin lispro (Humalog) and insulin aspart (Novolog). All three have a more rapid onset and shorter duration of action than regular human insulin. Rapid-acting insulin analogs are generally taken immediately before meals and are usually combined with a long-acting basal insulin.

The FDA has approved lubiprostone (Amitiza - Sucampo/Takeda), a chloride channel activator, for treatment of chronic idiopathic constipation in adults. The only other prescription drug approved by the FDA for this indication (in 2004 for adults <= 65 years old) is tegaserod (Zelnorm), a partial agonist of serotonin that is also approved for constipation-predominant irritable bowel syndrome in women. Of course, numerous over-the-counter products are available for treatment of constipation.

Conivaptan hydrochloride (Vaprisol - Astellas), a vasopressin antagonist, has been approved by the FDA for short-term intravenous (IV) treatment of euvolemic hyponatremia in hospitalized patients. Euvolemic hyponatremia is most often caused by the syndrome of inappropriate ADH secretion (SIADH), or by hypothyroidism or adrenal insufficiency. The drug has not been approved for treatment of hypervolemic hyponatremia, which is associated with congestive heart failure (CHF), cirrhosis and renal disease. It should not be used in hypovolemic hyponatremia, such as occurs when fluid losses are...