any member of the subphylum Crustacea (phylum Arthropoda), a group of invertebrate animals consisting of some 45,000 species distributed worldwide. Crabs, lobsters, shrimps, and wood lice are among the best-known crustaceans, but the group also includes an enormous variety of other forms without popular names.
It is thought that infrequent, low-dose users may test positive for Xanax within urine for up to 4 days post-ingestion. Frequent, high-dose users of the drug may test positive for Xanax after a full week post-ingestion via a urinalysis. Results from a urinalysis can be confirmed with technology such as GC/MS.
P.S I do not take xanax on a regular basis. XANAX (alprazolam) HAS a duration of action of up to 6 hours. If you want to know how long after you take it can it be DETECTED, that's different. Most benzodiazapines, when taken on a regular basis, can be detected in the urine from 24 hours to 72 hours.anax stays in the body 4 - 6 hours depending on the individual. The second answer was correct and off a pharamacy site! YET ANOTHER ANSWER! GENERALLY speaking, how long a drug stays in your system is more likey linked to how long does the drug works in your system.