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How Long Do Benzodiazepines Stay in the System?

Benzodiazepines, or benzos, are one of the most powerful tranquilizer sedatives prescribed by doctors. As a central nervous system depressant, benzos are highly effective. Benzos vary in use, active times and addictive qualities. It depends on the person and the drug how long it stays in the system.

Benzodiazepine Use

Medically, benzos are prescribed to induce sleep, relieve anxiety, sedate, treat muscle spasms and prevent seizures. Benzos are prescribed during alcohol withdrawal or used to treat anxiety related disorders. Recreationally, people take benzos for sedative effect or to enhance the effects of alcohol or opioids.

Peak Levels and Half Life

Peak levels and drug half life of benzos depends on the drug prescribed, dosage, interval between doses and route of administration. Longer half-life benzodiazepines have a more sustained effect. In general, benzos are divided into three categories:

  • Ultra short acting benzos – half life is less than 5 hours
  • Short acting and intermediate benzos – class of benzos have half-life values from 5-24 hours and can be dosed more frequently. Accumulation during multiple dosage is less extensive than with long-acting group
  • Long acting benzos – half-life values usually exceed 24 hours and drugs in this category have long acting pharmacologically active metabolites which accumulate extensively during multiple dosage

Benzodiazepine Drug Testing

Benzodiazepine drug testing is now part of most routine drug screens. Most standard drug screens can distinguish between different benzodiazepines. Since a number of these share common pathways of metabolism it is not possible to test for abuse of specific benzodiazepines.

Addiction to benzos can create many challenges for a person in work and at home. It is difficult to quit without the right support help of people in a social network. It is possible to get past addiction to benzos with the right treatment plan and support.


If you suspect a loved one is struggling with addiction to benzos or other drugs, now is the time to seek help.  Harmony Place can help you in the fight against addiction. Contact us at 1-888-789-4330 to find out how we can help support you or your loved one in seeking treatment.