Klonopin (clonazepam) typically stays in the system for about 6 to 9 days after the last dose, based on its long elimination half-life of approximately 30 to 40 hours. It generally takes around 5 half-lives for the drug to be mostly eliminated from the body
. Detection times vary by the type of drug test:
- Urine tests can detect Klonopin and its metabolites for about 4 days up to 2 weeks, with some sources noting detection up to a month in urine under certain conditions
- Blood tests usually detect it for 1 to 4 days
- Saliva tests can detect it for about 5 to 6 days
- Hair follicle tests can detect Klonopin for up to 90 days (3 months)
Several factors influence how long Klonopin stays in your system, including:
- Dosage and frequency of use (higher doses and frequent use prolong detection)
- Duration of use
- Age and metabolic rate
- Liver function and overall health
- Use of other drugs
Because Klonopin accumulates in the body and has a long half-life, it can take from about 4 to 14 days or longer to be fully cleared. In some cases, especially with heavy or prolonged use, traces may be detectable for weeks or even a month
. In summary, Klonopin’s effects last up to 12 hours, but the drug itself can remain in your system for about 1 to 2 weeks, with detection windows varying widely depending on the test and individual factors. Hair tests can detect use for up to 3 months
