Many physicians believe that antimicrobial prophylaxis before procedures that may cause transient bacteremia can prevent endocarditis and prosthetic joint infection in patients at increased risk for these disorders. The effectiveness of this common practice has never been established by controlled trials in humans.

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.

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.

A new once-daily, low-dose oral formulation of doxycycline monohydrate (Oracea - CollaGenex) has been approved by the FDA for treatment of inflammatory papules and pustules associated with rosacea in adults.

Infertility occurs in about 15% of couples. About one-third of cases are due to problems with ovulation or other female factors, another third are due to a male infertility factor, and the remaining third are unexplained. In older women, unexplained infertility is probably caused by diminished quality and quantity of oocytes. The first approach to treatment of female-factor infertility generally is the use of drugs that stimulate oocyte production.

The FDA has approved sodium zirconium cyclosilicate (Lokelma – AstraZeneca), an oral potassium binder that exchanges hydrogen and sodium for potassium in the gastrointestinal (GI) lumen, for treatment of non-life-threatening hyperkalemia in adults. Sodium zirconium cyclosilicate (SZC) is the third drug to be approved for this indication; sodium polystyrene sulfonate and patiromer (Veltassa) were approved earlier.

Cytomegalovirus immune globulin (CMVIG) for intravenous administration is now available in the USA on an investigational basis (FE Young and SL Nightingale, JAMA, 260:224, July 8, 1988) for prevention of cytomegalovirus (CMV) infection in CMV-seronegative renal transplant recipients who receive a kidney from a seropositive donor. CMVIG contains IgG antibodies from a pool of healthy donors with high titers of antibodies against CMV. The drug can be obtained from the Massachusetts Department of Public Health Biologic Laboratories (617-522-3700, extension 264) or the American Red Cross...

A recent report in the New England Journal of Medicine suggested that in children with bacterial meningitis, adding the corticosteroid dexamethasone (Decadron; and others) to antibiotic treatment could decrease the incidence of moderate or severe hearing loss.

Betaine (Cystadane - Orphan Medical), an orphan drug, has recently been marketed for treatment of homocystinuria, a genetic disorder. Patients with homocystinuria frequently have premature atherosclerosis and thromboembolism, and may also have lens dislocations, skeletal abnormalities and mental retardation (SH Mudd et al in CR Scriver et al, eds, The Metabolic and Molecular Bases of Inherited Disease, 7th ed, New York:McGraw Hill, 1995, page 1279).

Many readers have asked the Medical Letter to evaluate St. John's wort, an herbal extract now widely sold in health food stores and pharmacies, for its effectiveness and safety in the treatment of depression. St. John's wort is licensed in Germany for treatment of anxiety, depression and insomnia. In the USA, it is considered a dietary supplement and has not been evaluated by the FDA.