I had the shots and the only "side effects" i had was the pain (the 2nd was the worst pain). I think it mostly depends on the person, ya know? Definitely know your allergies and do research on it if you're that worried. I think it was the best thing i could've done before becoming "active" because Cervical Cancer runs in my family.. Both my aunt and my mother had cells and had to get them removed sooo, i definitely wasn't taking THAT chance. A few types is better than none if you ask me.