by Virginia Hopkins
The research is contradictory, the benefits are debatable and the threat of drug resistant viruses is real.
- Oseltamivir Phosphate (Tamiflu)
- Zanamivir (Relenza)
What Do They Do in the Body?
Both drugs are neuraminidase inhibitors. They inhibit enzyme activity in flu viruses, which in turn inhibits their growth and spread. Relenza is inhaled and Tamiflu is taken as a pill. They have to be taken within 36 to 48 hours of the onset of flu symptoms to be effective. Even when taken within this time frame, studies show only a one to one and a half day shortening of the illness’ duration on average.
Keep in mind that these medications do not prevent you from passing the flu on to others.
Although Tamiflu has been approved for preventing the flu, studies suggest only a small benefit of neuraminidase inhibitors for prevention, if any at all.