You may think the only way the police can arrest you for driving while intoxicated is if your blood alcohol concentration (BAC) is over 0.08 percent. The truth is that any kind of negligent driving that is a result of any level of intoxication could result in a DUI.
Even if you're only driving buzzed, it still isn't okay if that buzz is making you a danger to others. Noticeable impairment puts you at risk of a DUI. Why? You could have combined prescription drugs with alcohol, for example, which would be enough for a charge for driving under the influence of drugs if you were intoxicated and clearly impaired. Your BAC doesn't have to be over 0.08 for that charge to stick.