The FDA has issued a Public Health Alert to notify prescribers and pharmacists about 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.
According to the Public Health Alert, prescribers should avoid prescribing Tamiflu oral suspension in teaspoons, as this can lead to inaccurate dosing. If a prescription is written in teaspoons, the pharmacist should convert the volume to mL and ensure that an appropriate measuring device, such as an oral syringe calibrated in mL, is provided.
A letter has been sent to health care professional and pharmacists alerting them to this situation.
Read the complete MedWatch 2009 Safety summary, including links to the FDA Public Health alert, Dear Healthcare Professional letter [Roche] and Information for Pharmacists [CDC], on the FDA web site.