that is difficult to say but at least some of the tamiflu may have been absorbed. you are probably taking tamiful twice per day for five days so you can wait until the next dose is due. hopefully you will not vomit this one. i do not feel that taking an extra dose now would be prudent. if for some reason that you vomit again you need to consult your treating medical provider.
i vomited within an hour of taking tamiflu. is it still effective?