Can i take tamiflu if im on ms drug tysabri (natalizumab)?

Yes, but see below: We have good evidence that flu vaccines with dead viruses are effective with tysabri (natalizumab).. Tamiflu is an antiviral med that may alleviate some of flu symptoms and shorten duration, and would be unlikely to cause problems with tysabri (natalizumab). Might be wiser, though, to get a flu shot, and avoid nasal vaccine, as it is a live attenuated virus and adds risk.