Lorazepam (Ativan): Uses, Dosage, Risks, and What to Expect

Lorazepam (brand name: Ativan) is a benzodiazepine (intermediate-acting). Lorazepam enhances GABA-A receptor activity, increasing inhibitory signaling throughout the central nervous system. It has intermediate potency and duration among benzodiazepines. Unlike diazepam and many other benzodiazepines, lorazepam is metabolized by direct glucuronidation (Phase II metabolism) rather than CYP450 oxidation. This makes it one of the safest benzodiazepines in patients with liver disease, the elderly, and those on multiple medications, as its metabolism is less affected by hepatic impairment and drug interactions.

• Anxiety disorders (short-term relief)
• Insomnia due to anxiety
• Preoperative sedation
• Status epilepticus (IV formulation)

Common off-label uses:

• Acute agitation (IM/IV — widely used in emergency settings)
• Alcohol withdrawal
• Chemotherapy-induced nausea
• Catatonia (IV lorazepam is the first-line diagnostic and treatment tool)
• Akathisia
• Panic attacks (acute)

Anxiety: 0.5-2 mg 2-3 times daily. Insomnia: 1-2 mg at bedtime. Acute agitation: 0.5-2 mg IM/IV. Catatonia: 1-2 mg IV (lorazepam challenge test). Status epilepticus: 4 mg IV. Elderly: start at 0.5 mg. Maximum typically 6-10 mg/day.

Oral: 15-30 minutes. IM: 15-30 minutes. IV: 1-5 minutes. Duration: 6-8 hours.

• Sedation and drowsiness
• Dizziness
• Weakness
• Unsteadiness
• Memory impairment (anterograde amnesia)
• Cognitive slowing

• Physical dependence (can develop within 2-4 weeks of daily use)
• Severe withdrawal (seizures, delirium, psychosis if stopped abruptly)
• Respiratory depression (especially with opioids — FDA black box warning)
• Paradoxical disinhibition
• Falls and fractures in elderly
• Neonatal withdrawal if used in late pregnancy

Dangerous with opioids (respiratory depression — black box warning). Additive sedation with alcohol, antihistamines, and other CNS depressants. Key advantage: minimal CYP450 interactions since it bypasses oxidative metabolism. Probenecid and valproate can increase levels.

Category D. Risk of oral clefts with first-trimester use. Neonatal withdrawal and 'floppy infant syndrome' with late-pregnancy use. Avoid if possible.

Taper gradually — 10-25% reduction every 1-2 weeks. Faster tapers risk seizures and severe withdrawal. Its intermediate half-life makes tapering somewhat easier than alprazolam but harder than diazepam.