Roche addressed Tamiflu dosing discrepancies

September 30, 2009

Roche Laboratories recently released a statement to healthcare professionals regarding Tamiflu (oseltamivir phosphate) recommendations. Specifically, the company said there have been cases where the units of measure in the instructions on the prescription label have not matched the units of dosing devices.

Roche Laboratories recently released a statement to healthcare professionals regarding Tamiflu (oseltamivir phosphate) recommendations. Specifically, the company said there have been cases where the units of measure in the instructions on the prescription label have not matched the units of dosing devices.

The company said pharmacists should be aware that the oral dosing dispenser provided with the drug for oral suspension is marked with 30 mg, 45, mg, and 60 mg graduations, instead of milliliters or teaspoons. Dose recommendations in the dosing tables in the Tamiflu package insert are provided in milligrams.

Roche’s comment advised that if prescription instructions specify administration using milliliters or teaspoons, then the device included in the product package should be removed and replaced with an appropriate measuring tool. According to a letter to the editor in the New England Journal of Medicine, the issue has opened the possibility up to “serious potential for dosing errors in children prescribed Tamiflu.”

In one case described in the letter, a medication bottle was accompanied by a prepackaged syringe with markings of 30, 45, and 60 mg. The label attached by the pharmacy specified the dose in volume units. But the syringe provided only markings in mass units.

“Most families and caregivers would not be able to identify or perform the cumbersome calculations required to administer Tamiflu safely to children because the instructions on the pharmacy label, on the manufacturer’s printed label and in the accompanying consumer medication information and the prepackage dosing syringe are misaligned,” the letter to the editor read.

Pharmacists seeking additional information should visit www.rocheusa.com/products/tamiflu.