Several people responded that driving under the influence of any "awareness altering" drug is illegal. I agree. I chose that term because it applies to alcohol, weed, LSD, PCP, and, yes, many pain-relieving prescription drugs. The very nature of the pain relief goes hand-in-hand with changes in brain function. Therefore, your driving skills will not be as sharp as necessary to be a safe driver.

The exact maximum limits or a drug in your system and the related consequences will vary from state to state. It is possible to have a small amount in your system and not be impaired, as in alcohol use. Just like drinking, though, you can sometimes tell when you have “had too much” but not always. Many people who are way over the legal limit for alcohol think that they “are fine.”

cz said that it is the same as driving drunk. That is very true. Most states do not differentiate from one chemical to another – only that the driver was not in total control.

Mike