Our article on Antiviral Drugs for Prophylaxis and Treatment of Influenza (Med Lett Drugs Ther 2005;47:93) mentioned possible use of amantadine (Symmetrel, and others) and rimantadine (Flumadine, and others), but warned that the incidence of resistance has increased substantially. The CDC recently issued a Health Alert (www.cdc.gov) saying that current evidence indicates that a high proportion of circulating influenza A viruses in the US are now resistant to amantadine and rimantadine and they should not be used for this indication, at least this year. Click here to go to this update...

The FDA has approved crofelemer (kroe fel’ e mer; Fulyzaq – Salix), a chloride channel inhibitor derived from the red sap of the South American plant Croton lechleri, for symptomatic relief of noninfectious diarrhea in patients with HIV taking antiretroviral drugs. It is the first drug approved for relief of antiretroviral-induced diarrhea and the first oral botanical drug approved by the FDA.

The FDA has approved an over-the-counter (OTC) 0.025% ophthalmic formulation of the selective alpha₂-adrenergic agonist brimonidine tartrate (Lumify – Bausch & Lomb) for treatment of ocular redness in adults and children ≥5 years old. Lumify is the first brimonidine product to be approved for OTC use.

Fluticasone furoate nasal spray (Veramyst - GSK) is now available for once-daily treatment of seasonal and perennial allergic rhinitis in adults and children ≥2 years old. It is similar to fluticasone propionate nasal spray (Flonase, and others), which is now available generically.

Infertility occurs in about 15% of couples. About one third of infertility is due to problems with ovulation or an anatomic abnormality of the fallopian tube or peritoneum, such as scarring, adhesions or endometriosis. Another third is due to a male infertility factor, most commonly insufficient sperm production or abnormal motility or morphology. The remaining third is unexplained. In older women unexplained infertility is probably caused by diminished quality and quantity of oocytes, decreased implantation and spontaneous pregnancy wastage.

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.

A biodegradable polymer 'wafer' (Gliadel - Rh ne-Poulenc Rorer) impregnated with the alkylating agent carmustine (BCNU; Bicnu) has been marketed in the USA for local treatment of recurrent glioblastoma multiforme that requires re-operation. The dime-sized polyanhydride wafers are implanted into the surgical cavity left behind after resection. Release of the alkylating agent directly into the area of the tumor bypasses the blood-brain barrier (H Brem and R Langer, Sci Med, 3:1, 1996).

Brinzolamide (Azopt - Alcon), a thieno-thiazine-6-sulfonamide carbonic anhydrase inhibitor, has been approved by the FDA in a 1% ophthalmic suspension for treatment of elevated intraocular pressure due to ocular hypertension or open-angle glaucoma. Brinzolamide is the second FDA-approved topical carbonic anhydrase inhibitor. Dorzolamide (Trusopt) was approved earlier (Medical Letter, 37:76, 1995).

Increased resistance of pneumococci to antimicrobial drugs may encourage more extensive use of pneumococcal polysaccharide vaccine.

The US Public Health Service Advisory Committee on Immunization Practices has recently published new recommendations for prevention and control of meningococcal disease in college students.