Home › Compound Library › Lorazepam (Ativan)

Lorazepam (Ativan)

Benzodiazepineprescriptionoral · predicted

Intermediate-acting benzodiazepine (GABA-A positive allosteric modulator). Unlike most benzodiazepines, metabolized only by glucuronidation (no CYP450 involvement) — no active metabolites and minimal drug interactions. Preferred benzodiazepine in hepatic impairment and elderly. Used for acute anxiety, status epilepticus (IV), alcohol withdrawal, and procedural sedation. Available PO, IM, and IV. Risk of dependence with chronic use.

Projected serum levels — 1 mg, twice daily

Lorazepam (Ativan)
Lorazepam (Ativan) modeled serum levels, 1 mg twice daily over 15 days Population-based pharmacokinetic estimate. Steady state reached after approximately 3 days. 0 0.50 1 1.5 2 Day 0 Day 4 Day 7 Day 11 Day 15 Time on a regular schedule ≈ steady state · day 3
Lorazepam (Ativan) modeled serum levels with a loading dose of 2.6 mg, then 1 mg twice daily The first dose is larger so levels approach steady state faster. 0 0.50 1 1.5 2 Day 0 Day 4 Day 7 Day 11 Day 15 Time on a regular schedule

Maintenance schedule: 1 mg twice daily (oral).

Loading schedule: 2.6 mg on day 1, then 1 mg twice daily — reaching therapeutic levels sooner.

Modeled steady state after ~3 days: peak ≈ 2.0 mg, trough ≈ 1.4 mg body load. Population-based estimate over 15 days for a 1 mg dose at a 70 kg reference body mass — the interactive app scales curves to your doses, timing, and body mass.

Key facts

Category
Benzodiazepine
Route modeled
Oral
Model confidence
predicted
Half-life
12 h
Common dose
1 mg
Suggested maximum
10 mg/day
Reference dose range
0.25–10 mg (single dose)
Suggested cadence
twice daily
Validated against
2 mg oral — Cmax 0.020 mg/L at 2 h

Documented interactions

  • caution
    St. John's Wort (Hypericum perforatum) + Lorazepam (Ativan) Depletion

    CYP3A4 induction reduces benzodiazepine levels.

  • watch
    CBD (Cannabidiol) + Lorazepam (Ativan) CYP inhibition

    CBD (Cannabidiol) reversible_inhibitor of UGT2B7 predicted to change Lorazepam (Ativan) AUC by ~1.17x

  • watch
    GABA (Gamma-Aminobutyric Acid) + Lorazepam (Ativan) Stacked effects

    GABA (Gamma-Aminobutyric Acid) and Lorazepam (Ativan) both push the gaba a in the same direction.

  • watch
    Ivermectin (Stromectol) + Lorazepam (Ativan) Stacked effects

    Ivermectin (Stromectol) and Lorazepam (Ativan) both push the gaba a in the same direction.

  • watch
    L-Theanine + Lorazepam (Ativan) Stacked effects

    L-Theanine and Lorazepam (Ativan) both push the gaba a in the same direction.

  • watch
    Taurine + Lorazepam (Ativan) Stacked effects

    Lorazepam (Ativan) and Taurine both push the gaba a in the same direction.

Serum checks 6 modeled interaction pairings for lorazepam (ativan) across your whole stack — absorption conflicts, enzyme inhibition, and nutrient depletion included.

Research behind this entry

  1. Lorazepam versus diazepam for the treatment of status epilepticus: a meta-analysis Prasad K et al. · Seizure, 2005 DOI

    Meta-analysis demonstrating lorazepam was superior to diazepam for terminating status epilepticus (OR 1.52), with longer duration of action and less respiratory depression, establishing it as first-line IV…

  2. Clinical pharmacokinetics of lorazepam: a review Greenblatt DJ et al. · Journal of Clinical Psychiatry, 1977 DOI

    Foundational PK study establishing lorazepam half-life of 10-20 hours (mean 12h), 90% bioavailability, exclusively UGT metabolism with no active metabolites, and no significant accumulation with repeated dosing.

  3. Pharmacological interventions for benzodiazepine discontinuation in chronic benzodiazepine users Baandrup L et al. · Cochrane Database of Systematic Reviews, 2018 DOI

    Cochrane review documenting the psychological and physiological dependence that develops with long-term lorazepam and other benzodiazepine use, and the difficulty of discontinuation even with pharmacological support.

  4. Randomized, double-blind comparison of lorazepam and diazepam for the treatment of alcohol withdrawal delirium Saitz R et al. · Journal of General Internal Medicine, 2010 DOI

    RCT comparing benzodiazepines for alcohol withdrawal in ICU patients found lorazepam effective with similar efficacy to diazepam and preferred in hepatic impairment due to its simpler UGT-only metabolism.

4 published studies referenced in the app, each with a plain-language summary.