How Long Does Lorazepam Stay in Your System? Half-Life & Detection Times

Lorazepam is classified as a “benzodiazepine.” It’s in the same class of drugs as other “benzos” like Alprazolam (Xanax) and Diazepam (Valium). Doctors prescribe these medications to primarily treat anxiety disorders, and they’re incredibly effective drugs for this purpose.

Lorazepam, known by the brand name “Ativan,” helps with anxiety management and it’s also useful for inducing sleep. Benzos work by attaching to GABA-A receptors on neurons, creating a sedative effect in the patient that calms the nervous system.

Benzodiazepines are one of the most misused and abused medications in the United States. While Ativan addiction is less common than Xanax addiction, there are tens of thousands of people who misuse or abuse the drug every day.

Understanding Ativan’s mechanism of action, half-life, and detection time is an important part of educating yourself on the properties of this drug, and why it’s so important to get into an inpatient recovery program if you find yourself dependent on or addicted to this medication.

How Long Does Lorazepam Last in Your System?

In medical settings, doctors administer lorazepam to sedate patients, and to treat issues like insomnia, anxiety, and nausea. The clinical research on the drug shows that it has a half-life of 12 to 18 hours (depending on the study you review), which isn’t as long as Valium, but longer than Xanax.

The reason for the discrepancy in half-life comes from the metabolite, “Lorazepam Glucuronide,” which has an 18-hour half-life, and may be detected in drug tests. The half-life of a drug refers to the time it takes for the concentrations of the drug in the system to reduce by half.

That means that lorazepam clears from your system and is usually undetectable around 48 to 72 hours after taking your last dose (averaging around 2.75 days for oral preparations of the drug).

It’s a slow-acting medication and most users notice peak effects of the drug two hours after taking it. The GI tract absorbs the medication and floods it into the bloodstream, while the liver undertakes the duty of excreting the drug and its metabolites from the body.

Doctors will usually prescribe patients with two to three doses per day, with the concentration of the drug dependent on factors like the patients age and weight.

Users notice that the effects of the drug wear off after 6 to 8 hours, and they’ll need to take another dose to maintain serum levels in the blood. These numbers apply to oral preparations of lorazepam. Intravenous applications can increase the duration of its effects on the body and brain.

Unlike other benzo such as Klonopin, Ativan doesn’t accumulate readily in the body. Still, doctors will prescribe short courses of the drug as it has a high propensity to cause dependency with prolonged use, possibly resulting in the user becoming addicted to the medication.

If the user does experience dependency and/or addiction, they require medically assisted detox protocols in inpatient treatment settings to help their body wean itself off the drug. Suddenly stopping its use if you’re a long-time addict or user may result in severe adverse withdrawal effects, such as seizures, rebound anxiety, tachycardia, heart palpitations, and many more dreadful symptoms.

Using Lorazepam for Alcohol Detox and AWS

Clinical research on lorazepam published in the journal “Oxford Academic,” shows that lorazepam is effective in treating patients dealing with Alcohol Use Disorder (AUD). The drug is so efficacious that it can reduce the effects of “Alcohol Withdrawal Syndrome” (AWS), even with small doses.

Lorazepam is suitable for use in outpatient Medically Assisted Treatment (MAT) recovery programs and preferred to drugs like disulfiram and naltrexone or disulfiram. Lorazepam reduces cravings for drugs and alcohol in the first week of detox and is usually taken in higher doses during the initial phase of this process.

While the drug doesn’t entirely remove the symptoms of AWS, it makes the experience much easier on the user, helping them maintain their composure and mental health during the detox process. Lorazepam isn’t unique in this application. Many MAT protocols involve the use of benzos because they’re highly effective at limiting the effects of AWS in recovery.

That said, Lorazepam, like all benzodiazepines, is not suitable for use in outpatient home detox protocols. It must be administered in a controlled setting to ensure absolute safety for the user. If the user relapses and starts combining alcohol and lorazepam, it can lead to life-threatening effects, such as “respiratory depression,” where the user stops breathing.

Doctors will lower the dose after the first week of administration in a medically managed detox. The patient may continue the use of the drug during their inpatient treatment.

Comparing Lorazepam Vs Diazepam for AWS Treatment

Until the late 2010s, the “front-loading” of intravenous diazepam (valium) was the benchmark treatment for AWS. Before then, there was little research on using lorazepam for the same application, and that’s understandable—diazepam was the gold standard for a reason—it works.

However, MAT recovery programs started the use of IV front-loaded lorazepam administrations in 2017 due to a shortage of diazepam across the United States. Research results show that using the drug for AWS treatment was as efficacious as diazepam, and even reduced CIWA-Ar scores more than IV diazepam.

Lorazepam front-loading proves to be as efficacious as diazepam for controlling the feelings of agitation in AUD patients undergoing medically assisted detox protocols. The only drawback to the research is that lorazepam administration tended to over-sedate the patient in the first 24 hours after starting the protocol. Therefore, doctors must account for this delayed action when administering the drug in controlled settings.

Mechanism of Action

Neurons are responsible for delivering electrical charges throughout the nervous system and when they are over-excited they can cause the onset of seizures. It’s common for AUD patients to experience a state of delirium caused by sudden cessation of alcohol use, resulting in the potential for seizures and coma in the patient when they experience AWS.

Lorazepam calms the patient and reduces neuron activity by binding to the GABA (γ-aminobutyric acid) receptors in the nervous system and brain, reducing feelings of anxiety, tension, and delirium associated with AWS. Lorazepam’s mechanism of action mimics the body’s natural mechanism.

When neurons in the brain experience a sudden massive influx of chloride ions via lorazepam IV therapy, they inhibit the postsynaptic GABA-A ligand-gated chloride channel. This effect enables the influx of chloride ions to increase the membrane potential. This hyperpolarization effect creates a state of sedation in the patient’s cerebral cortex and amygdala, reducing seizure risk while soothing anxiety.

Lorazepam Tmax and Clearance Times – Influencing Factors

Lorazepam is commonly used as an intravenous treatment in AUD withdrawal protocols. A 2018 review by David Hui shows that the onset time for lorazepam varies depending on the method of administration used in the MAT AWS protocol.

The drug takes two hours to reach peak serum concentrations (Tmax) when administered intravenously but patients may notice the effects in as little as one to three minutes, depending on their weight and physical condition.

Intramuscular Tmax can take up to three hours to show its effects in the patient and sublingual administration can take as little as an hour before the patient starts noticing its effects on their physiology.

As we mentioned earlier, the clearance time for lorazepam is approximately 12 hours. We say “approximately” because there are a slew of factors contributing to decreased clearance times in users.

Like we said, lorazepam glucuronide metabolites have an 18-hour half-life, and require four to five half-lives to clear the drug completely from the system. That means that it’s completely out of your body within 48 to 72 hours after your last dose.

While half life plays a significant role in determining the clearance time for the drug, there are other influencing factors that might slow down the process. Let’s examine the physiological and secondary factors that affect the clearance time for the drug.

Physiological Tmax and Clearance Factors

Weight – The patients BMI plays a role in speed of metabolism and how long it takes lorazepam to reach Tmax. The heavier they are, and the more body fat they have, the longer it takes for the body to reach peak serum levels, and the longer it takes to clear the drug from their system.

Age – Our metabolism slows with age and patients over 40, or those with metabolic syndrome causing a slowing of metabolic rate take longer to reach Tmax and up to 20% longer to clear the drug.

Genetics – Our genetic makeup determines our metabolic rate, and some people have a naturally slower metabolism than others.

General Health – The persons activity level, personal habits, and their self-care all play a role in clearance times for the drug. Lorazepam is a teratogenic compound and women who are pregnant or trying to fall pregnant should consult with their doctor before starting a lorazepam protocol.

Secondary Tmax and Clearance Factors

Food and Hydration – Eating meals high in fat and large quantities of food slow digestion and the absorption of lorazepam in the gut, affecting peak concentration levels in the blood and clearance times.

Method of Administration – As mentioned earlier, the method of administration plays a role in Tmax and clearance of lorazepam from the patient’s system.

Dosage and Frequency – Higher doses and more frequent dosing of the drug slow clearance times. While Lorazepam demonstrates that it doesn’t readily accumulate in tissues, it may accumulate slightly in people with a high BMI, resulting in longer clearance times.

History of Misuse or Abuse – Patients with a history of lorazepam or benzo abuse can build a tolerance to the drug, interfering with their treatment.

Interactions with other Drugs – The liver processes lorazepam metabolites and patients using other drugs that undergo the same clearance method may interfere with Tmax and clearance times. There are studies showing that combining alcohol with lorazepam use increases clearance times by up to 18%. Drugs like theophylline, valproate, and probenecid can alter lorazepam half-life and clearance times.

Testing Methods and Detection Times for Lorazepam

There are four methods for detecting the presence of lorazepam metabolites in users. Each test has its limitations and advantages, and we’ll walk you through them in this section.

Detection Times in Urine

Urine testing is the most common detection method for all drugs. It’s affordable and non-invasive, making it the gold standard for detection practices. Lorazepam will show up in the patients’ urine up to six days after the last dose, with the lorazepam glucuronide metabolites remaining in the patients urine for up to nine days after their last dose.

Detection Times in Blood

Blood tests detect Ativan six hours after the patient’s first dose and up to six days after their last dose. Blood testing is considered invasive and usually limited to law enforcement testing practices.

Detection Times in Saliva

The drug clears from saliva fast. It takes 15 minutes to show up in the saliva after the patient’s first dose and clears from saliva eight hours after the patients last dose.

Detection Times in Hair

Hair follicle testing provides the longest detection time, with the drug remaining in the hair follicles for up to 30 days after the patient’s last dose. It’s important to note that metabolites will only show up in hair follicles a week after taking the dose.

Wrapping Up – Is Lorazepam Right for You in AUD Withdrawal?

While lorazepam is a fantastic alternative for MAT AWD protocols, it usually takes a backseat to diazepam. Still, there are many rehab centers using this drug in place of diazepam, in controlled settings. Some recovery facilities actually prefer the use of lorazepam over diazepam due to the front-loading effect we discussed earlier, and its ability to sedate the patient.

Doctors will rigorously assess the patient upon admission to a medically assisted withdrawal protocol to determine the right approach to their treatment. Lorazepam is definitely on the table and a good choice but considering the interaction of this drug with other medications, it might not always be the safest option in some cases.