September 26, 2009
Today the U.S. Food and Drug Administration (FDA) alerted prescribers and pharmacists to potential dosing errors with Tamiflu (oseltamivir) for Oral Suspension. U.S. health care providers usually write prescriptions for liquid medicines in milliliters (mL) or teaspoons, while Tamiflu is dosed in milligrams (mg). The dosing dispenser packaged with Tamiflu has markings only in 30, 45 and 60 mg. The Agency has received reports of errors where dosing instructions for the patient do not match the dosing dispenser.

Health care providers should write doses in mg if the dosing dispenser with the drug is in mg. Pharmacists should ensure that the units of measure on the prescription instructions match the dosing device provided with the drug.

If prescription instructions specify administration using mL, the dosing device accompanying the product should be replaced with a measuring device (e.g., a syringe) calibrated in mL.

Visit the FDA Web site for additional information, including Tamiflu dosing for children over one year of age.