The FDA has warned that prolonged use of a proton pump inhibitor (PPI) can lead to hypomagnesemia.1 Normal serum concentrations of magnesium are 0.7-1.0 mmol/L. About 30 cases of severe hypomagnesemia (<0.5 mmol/L) have been reported in long-term PPI users; when the PPI was stopped, serum magnesium levels returned to normal in less than 2 weeks.2-5 The exact mechanism is unknown, but in some patients PPIs apparently interfere with active transport of magnesium across the intestinal wall or cause excessive loss into the intestinal lumen.6 Hypomagnesemia is often accompanied by hypocalcemia...

The transdermal patch formulation of the anticholinergic drug oxybutynin (Oxytrol – Watson) is now available over the counter (OTC) as Oxytrol for Women (MSD) for use in women with overactive bladder (OAB). It is the first treatment for OAB to become available OTC. Oxybutynin remains available only by prescription for men.OAB, characterized by symptoms of urgency, frequency, and incontinence with no obvious cause, occurs mainly in older women.1 Behavioral modification, including fluid schedules, timed voiding, pelvic exercises, and urge suppression, is usually tried first.Anticholinergic...

A reader commenting on our Treatment of Lyme Disease article (Med Lett Drugs Ther 2016; 58:57) objected to a footnote in the table advising against use of doxycycline in children <8 years old. This warning has been included in the labeling of all tetracyclines since 1970 when it was recognized, after decades of use, that these drugs caused permanent staining and enamel hypoplasia of developing teeth. The CDC recently stated that short courses of doxycycline, which was first marketed in the US in 1967 and has less affnity for calcium than other tetracyclines, have not been shown to cause...

Lisdexamfetamine dimesylate (Vyvanse - Shire), a prodrug in which d-amphetamine is covalently bonded to L-lysine, has been approved by the FDA for treatment of attention-deficit/hyperactivity disorder (ADHD) in children 6-12 years old. It was designed to have less potential than amphetamine itself for abuse, diversion or overdose toxicity. Like methylphenidate and amphetamines, lisdexamfetamine is a Schedule II controlled substance.

The FDA has approved lacosamide (Vimpat - UCB Pharma) for oral or intravenous (IV) use as add-on therapy in adults with partial-onset seizures.

The FDA has approved the marketing of pitavastatin (Livalo – Kowa), an HMG-CoA reductase inhibitor (“statin”), for treatment of primary hyperlipidemia or mixed dyslipidemia. It has been available in Japan since 2003. All of the statins now available in the US are listed in the table on page 58.

The FDA has approved the interleukin (IL)-23 antagonist risankizumab-rzaa (Skyrizi – Abbvie) for treatment of moderate to severe plaque psoriasis in adults. Risankizumab is the third IL-23 antagonist to be approved for this indication; guselkumab (Tremfya) and tildrakizumab (Ilumya) were approved earlier.

Topotecan hydrochloride (Hycamtin - SmithKline Beecham) was recently approved by the U.S. Food and Drug Administration for parenteral use as a single agent in patients with metastatic ovarian cancer refractory to other drugs. Initial treatment for metastatic ovarian cancer usually consists of cisplatin (Platinol) or carboplatin (Paraplatin) plus paclitaxel (Taxol) or cyclophosphamide (Cytoxan, and others).

Anagrelide (an ag' gre lide) hydrochloride (Agrylin - Roberts), a quinazolin derivative, has been approved by the FDA for oral treatment of essential thrombocythemia. Patients with this uncommon myeloproliferative disorder have an increased number of circulating platelets and are at risk for both thrombosis and hemorrhage.

The 0.15% nasal spray formulation of the H₁- antihistamine azelastine hydrochloride (Astepro Allergy; Children's Astepro Allergy – Bayer) is now available over the counter (OTC) for temporary relief of nasal congestion, runny nose, sneezing, and itchy nose due to allergic rhinitis in adults and children ≥6 years old. It is the first intranasal antihistamine to be approved by the FDA for OTC use. Other drugs that are available OTC for treatment of allergic rhinitis symptoms include oral antihistamines, intranasal corticosteroids, and mast cell stabilizers.