Drug Effects
The effects that drugs can have on an individual will vary dependent on the drug taken. For example, if you use amphetamine or cocaine you will experience an initial high where you feel exhilarated, feel alert and have high energy; however you will also be in danger of taking risks. Once the initial high has passed, you will begin to feel fatigued and drowsy and you may become restless, irritable and possibly aggressive - effects that, again, are not compatible with the safe control of a motor vehicle.
However, unlike alcohol, there is no specified limit for some drugs in the blood when it comes to driving and prosecution will depend not only the presence of the drug being detected in the blood/urine but also on any impairment being observed; by a medical examiner and/or any other witness (police or civilian).
In general drugs can be detected in the blood for up to 24 hours after ingestion, and can possibly be detected for days in the urine, as per the drug timelines.
