Tamiflu dispensers cause dosage confusion and errors

The U.S. Food and Drug Administration issued a public health alert Thursday after finding errors with the measurements on the dosing dispenser included in Tamiflu packaging. Tamiflu is the brand name of Oseltamivir, an antiviral prescription drug used to treat people infected with the influenza virus. Produced by Swiss global health care company F. Hoffman-La Roche Ltd., Tamiflu has been used extensively throughout the world during the last decade to help curb the spread of the flu virus within patients.

The FDA found that the dosage dispenser in Tamiflu packages have dosage markings in 30, 45, and 60 milligrams (mg). American health care providers normally write prescriptions for liquid medicines , such as Tamiflu, in milliliters (mL) or teaspoons. The discrepancy between the American standard and the metric dosing dispenser has caused confusion and led some patients to erroneously ingest the wrong amount of medicine. The FDA has received reports that the doctor’s dosing instructions do not match with the dosing dispenser.

The demand for Tamiflu is extremely high worldwide because of the spread of H1N1 Swine Flu and other strains of influenza. Rather than recall the drug, the FDA has chosen to alert doctors, pharmacists and the general public about the Tamiflu dispensers. The agency advises doctors to write Tamiflu prescriptions in milligrams if the dispenser with the drug is marked in milligrams. Pharmacists should also compare the health care provider’s dosing instructions with the Tamiflu dispenser to ensure they match.

The Centers for Disease Control and Prevention (CDC) expects that the United States will experience “an early, prolonged and severe” influenza season in which both the H1N1 virus and seasonal flu are active. The CDC requests that pharmacists prioritize prescriptions for Tamiflu, with highest priority given to patients who are hospitalized with the flu virus or sick with flu symptoms and at increased risk of developing serious complications. People most at risk are pregnant women, young children, people age 65 or older, and people with chronic health problems.