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Drug DUI: How long does a drug stay in your system?
Drug DUI: How long is a drug in your system?
Drug DUI: How long is a drug in your system – The Half Life
The half life of a medication is the time required for concentrations of the medication to decrease by half; typically serum concentrations. A drug like diazepam has a relatively long half life. Even using the most simplistic pharmacokinetic explanation ( one compartment zero order elimination ) serum concentration would decrease for example from 20 ng / ml to 10 ng/ml in approximately 40 hours ( using a standard half life value).
I have seen references in the literature to diazepam as having a half-life that ranges from 40 to 100 hours, and references to its “Duration of effect” or “Duration of action” as being approximately 3 hours.
Intoxication / DUI and How Long Drugs Are In Your System
That leads to a few questions about how that might relate into intoxication, for DUI or drunk driving purposes:
1. What is the correlation between half-life and duration of effect for a drug like valium? Why is duration of effect so much shorter than the half-life? For example, if it takes the body 40 hours to eliminate half the amount of diazepam present in the body. why doesn’t valium stay active for at least 40 hours?