I would really recommend that you follow through on some form of treatment for this shivering or this may develop into phobias of different sorts . You've provided a brief description for something that usually requires a 15 minute inquiry. At best, atleast discuss it with those close to you, whose opinion you trust, as to when and why this shivering starts and try to identify reasons behind it. Common wisdom, i trust, will prevail and help you resolve the problem. I would never advise taking any medicine you havent taken before, on the day of the interview. I called up someone who's specializing in psychiatry and he's advised that you start taking inderal 10mg ,one daily, three days before the interview, so that your body becomes accoustomed to any unpleasent side effects that may present themselves. On the day of the interview , take one 20mg tablet if you feel that 10 wouldnot be enough. Stop taking it after that. The drug is contra indicated in asthma so abstain from taking it altogether if you're a diagnosed asthmatic. The drug will provide syptomatic relief but you need to look into why and when these episodes of shivering and increased heart rate are precipitated. I hope i've been of help.Best of luck with the interviews.