Xanax is fast acting. Depending on the half life, the time it takes a drug to be reduced by half the concentration in the blood, the time it takes Xanax to leave the body can vary with age, weight, race, liver disease, smoking. Xanax is broken down in the liver and leaves the body through the kidneys.
In most cases it takes a healthy adult 6 to 12 hours for the drug to leave your system but it can be detected in hair for as long as the hair has been growing. The concentration is up to 25% higher in Asians compared to Caucasians.
Other things that control how long it takes Xanax to get out of your system is if you smoke or not, in a smoker it takes longer for the kidneys to get rid of it. Higher concentration of the drug is likely in an obese person because of fat around the liver it takes longer to metabolize up to 25% longer therefore taking longer for the kidneys to remove it from the body.
It can take up to 50% or higher for an elderly person to get Xanax out of the system. Because Xanax is broken down by the liver and eliminated by the kidneys the rate it leaves the body varies greatly from person to person but on average it leaves the body anywhere from 1 to 7 days so age, weight, race and overall health must be used to be able to give the right time it takes to rid the system.