Most people associate DUI charges with drinking and driving, but, in reality DUI means you are driving while under the influence of any type of substance that will interfere with your ability to drive. Example - there are some medications that will cause you to appear as a DUI suspect if you have a bad reaction to the medicine while driving. If you are tired you can appear as a DUI suspect. It depends on the situation and what you did before getting behind the wheel and what an Officer finds to determine whether or not you will be charged as a DUI suspect. However, alchol and drugs are the most common indicators, drugs being the worst and carry the greatest degree of the penalty. In the state of Nevade, you probably will be penalized less with drinking and driving, but, if an Officer finds 1 marijuana seed on you or in your vehicle, the penalty is more severe then driving drunk.
Check the laws for each state because they do vary from 1 degree to another.
here is a your answer. you can get it from this blog.