FDA Drug Safety Communication

FDA is informing the public of important product safety changes to the influenza drug Tamiflu (oseltamivir phosphate) for oral suspension. These changes are being made to reduce the possibility of prescribing and dosing confusion that can lead to medication errors. FDA has worked with the manufacturer, Genentech (part of the Roche Group), to make these changes.

- A change to the concentration of Tamiflu from 12 mg/mL to 6 mg/mL. The lower concentration of Tamiflu is less likely to become frothy when shaken, which helps to ensure an accurate measurement. The 12 mg/mL concentration will no longer be marketed after current supplies run out.

- A change in the measurements of the oral dosing device (graphic) from milligrams (mg = weight) to milliliters (mL = volume).

- A change in the dosing table for Tamiflu to include a column for the volume (mL) based on the new 6 mg/mL concentration. (Table 1)

- Revised container labels and carton packaging (graphic).

- Revised compounding instructions for pharmacies to prepare a 6 mg/mL oral suspension from Tamiflu capsules in an emergency situation only if the commercially manufactured Tamiflu for oral suspension is unavailable.

Genentech, the manufacturer of Tamiflu for oral suspension, plans to begin distribution of the new 6 mg/mL product in July 2011. The company has instituted a voluntary Take Back Program for wholesale buyers, distributors and pharmacies to remove the 12 mg/mL product from the marketplace. There are no quality issues with the 12 mg/mL product; it is still useable through its expiration date. However, FDA encourages participation in the Take Back Program to limit the potential for product confusion. The 12 mg/mL product will remain in the marketplace and in state or national stockpiles until current supplies expire. Therefore, it is important for healthcare professionals to be aware that a patient may potentially receive either concentration (6 mg/mL or 12 mg/mL) from their pharmacy during the next influenza season (2011-2012). Steps should be taken to avoid the potential for a medication error due to confusion between the two concentrations.

Healthcare Professionals should:

- include the new concentration (6 mg/mL) and dose in milliliters on all prescriptions for Tamiflu for oral suspension.

- be aware that pediatric strength Tamiflu capsules (30 mg and 45 mg) are available and have not changed. These capsules can be prescribed for pediatric patients who can swallow capsules. For patients who cannot swallow capsules, these can be opened and the capsule contents can be mixed with flavored foods (such as chocolate syrup or caramel topping).

- The new 6 mg/mL product contains an oral dosing device graduated in mL, whereas the old 12 mg/mL product contained an oral dosing device with dose markings in mg.

- It is possible that patients may get either concentration at the pharmacy during the 2011-2012 flu season; patients should be educated about this possibility to avoid medication errors.

- The two versions of the professional label may appear in circulation during the next influenza season (2011-12) and contain different dosing and compounding instructions for the oral suspension.

View the full FDA Drug Safety Communication on FDA.gov