I had botox from sept 2008 - sept 2009 with wonderful results & no side effects. I was getting it for free in exchange for outside work I was doing for my derm, who I have been seeing happily for years for other non cosmetic issues.
I got it again 3 weeks ago because I had a very important job interview. I got it on a Tuesday on on Saturday I woke up so ill with nausea & vertigo I ended up in the ER after my husband called 911. I had gotten dehydrated and couldn't stand up. My poor kids! And I was in such a panic because i had a serious career opportunity opening up to me and I couldn't afford to miss the interview. (Luckily, I got better enough to do well at the meeting)I had to see an ear nose throat specialist a week later who told me I had probably developed some antibodies to the Botox during the year I had taken off from it, and my immune system went into overdrive (my blood work from the ER showed an elevated white blood cell count) and caused the vertigo. He said he has seen it before. Said it can even cause Bell's Palsy in your face (where one side is paralyzed & droopy.)
I am better but not 100%, after 3 weeks of anti-virals and 8 days of steroids. My eyesight is still not tracking correctly, either. I look so much better with Botox, but I will never ever again in my lifetime get any more, or any other injectable, for that matter. It is not worth it. For a smooth forehead! Why was I so silly? My husband loves me the same with wrinkles, so do my kids.