With alcohol, there is a presumption limit of .08. With a blood test due to drugs, there is no presumptive limit, which means you have more leeway to argue your case. The State will have to prove beyond a reasonable doubt that your ability to operate a motor vehicle was affected.
Hire a lawyer immediately.
The DUI would not be different. You may have several defenses based on the facts that you are indicating. You should call a DUI lawyer. Most of us have a free initial consultation.
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