Tamiflu - Oseltamivir

Note to my patients: Tamiflu is an antiviral drug, not a vaccine against flu
This article from emedicine will help you.

Tamiflu

Inhibitor of neuraminidase, which is a glycoprotein on the surface of the influenza virus that destroys the infected cell's receptor for viral hemagglutinin. By inhibiting viral neuraminidase, release of viruses from infected cells and viral spread are decreased.
Effective against influenza virus types A and B.
Available as capsule and an Per Oral suspension.

Oseltamivir (Tamiflu) resistance has emerged in the United States during the 2008-2009 influenza season.
The CDC has issued revised interim recommendations for antiviral treatment and prophylaxis of influenza.
Preliminary data from a limited number of states indicate the prevalence of influenza A (H1N1) virus strains resistant to oseltamivir (Tamiflu) is high.
Because of this, zanamivir (Relenza) is recommended as the initial choice for antiviral prophylaxis or treatment when influenza A infection or exposure is suspected. A second-line alternative is a combination of oseltamivir plus rimantadine, rather than oseltamivir alone.
Local influenza surveillance data and laboratory testing can assist the physician regarding antiviral agent choice.


Pregnancy
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions
Caution in renal impairment (decrease dose if CrCl <30 mL/min), chronic cardiac or respiratory disease, and breastfeeding; may cause nausea or vomiting

Contraindication
Documented hypersensitivity