How long long does 10mg of diazepam take to get out of your system completely?

Benzodiazepines like diazepam can stay in the system a pretty long time. It depends on how much you take and for how long. Also your health, age, weight and metabolic rate play a part.

How long a drug stays in your system depends mainly on it's elimination half life - the time it takes for plasma drug levels to fall by half.
The elimination half life of the active metabolite of diazepam (N-desmethyldiazepam) is, on average, 100 hours.

It takes 5.5 x elimination half lives (hours) for a medicine to be cleared from your system, therefore diazepam or it's active metabolite will be in your system for 550 hours (5.5 x 100hrs) i.e. approximately 23 days.

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