Extremely important for passing your drug test successfully is information about how long do drugs stay in your system. Let’s consider several causes.
Firstly, let’s speaking about the most popular drug - how long does marijuana stay in system. That question is really hard . Remember, that nobody and nothing can say how long EXACTLY does THC (cannabis) stay in YOUR body (blood, urine). It depends on a lot of factors, such as human age, weight, metabolism, amount and potency of marijuana, etc. THC is fat soluble and an average, THC stays in your urine 7 days for single use and 30 days for habitual use. In your blood marijuana stays an average 2 days and in your hair THC detectable much longer –up to 90 days.
Amphetamines are water soluble and can detectable in your urine an average during 3-5 days after stop using. In your hair follicle these stay up to 90 days.
Opiates(Cocaine,Codeine,Morphine,Heroin) can be detectable in your urine in range of 2-5 days. Like another drugs, in your hair Opiates can stay up to 3 month.
And finally, we have to repeat, all the above facts are approximate and nobody and nothing can say how long EXACTLY do drugs stay in YOUR body (blood, urine,hair).