What is the maximum safe dose of lorazepam for a 17‑year‑old adolescent with acute psychosis requiring short‑term control of agitation?

Maximum Lorazepam Dose for a 17-Year-Old with Psychosis

For a 17-year-old adolescent with acute psychosis requiring short-term control of agitation, the maximum single dose of lorazepam is 5 mg, with doses repeated hourly as necessary, though lorazepam should not be used as monotherapy for psychotic agitation and is best combined with an antipsychotic. 1

Dosing Guidelines for Adolescents

Weight-based dosing is the preferred approach for adolescents:

• Standard dose: 0.05–0.1 mg/kg PO/IM/IV 1
• Maximum single dose: 5 mg 1
• Repeat interval: May repeat hourly as necessary 1
• Older adolescents (>16 years): Can receive adult-equivalent dosing when combined with antipsychotics 1

For a typical 17-year-old weighing 60–70 kg, this translates to approximately 3–7 mg per dose using weight-based calculations, though the absolute maximum single dose remains 5 mg. 1

Critical Limitations of Lorazepam Monotherapy

Lorazepam alone does not address the underlying psychotic symptoms that drive agitation in psychotic patients. 2, 3 The medication provides sedation but fails to treat hallucinations, delusions, or thought disorganization that perpetuate dangerous behavior. 2

Lorazepam is most effective when combined with an antipsychotic rather than used as monotherapy for psychotic agitation:

• Preferred combination for older adolescents (>16 years): Haloperidol + lorazepam or risperidone + lorazepam 1
• Haloperidol dose: 5–10 mg IM combined with lorazepam 2 mg 1
• Risperidone dose: 2 mg PO combined with lorazepam 2 mg 4, 5

Pharmacokinetics and Timing

Onset and duration vary by route:

• IV onset: 5–10 minutes 1
• IM onset: 15 minutes 1
• PO onset: 20–30 minutes 1
• Duration: 6–8 hours PO/IM 1

The relatively rapid onset makes lorazepam suitable for acute agitation, but the short duration means it does not prevent future disruptive episodes. 3

Safety Considerations Specific to Adolescents

Paradoxical disinhibition occurs more frequently in younger patients, particularly those with developmental disabilities. 1 This can manifest as increased agitation, aggression, or impulsivity rather than the intended calming effect.

Respiratory depression is a significant risk, especially when:

• Combined with antipsychotics 1
• Used in patients with underlying respiratory conditions 1
• Administered rapidly IV 1

Monitoring requirements include:

• Continuous observation for respiratory depression 1
• Assessment for paradoxical reactions 1
• Vital signs every 15–30 minutes initially 1

Common Pitfalls to Avoid

Do not use lorazepam as maintenance therapy for ongoing psychotic symptoms. 3 Data demonstrate it does not prevent future disruptive behavior and should be reserved for acute episodes only. 3

Do not exceed the maximum single dose of 5 mg even in larger adolescents, as higher doses increase adverse effects without proportional benefit. 1

Do not rely on lorazepam monotherapy when psychotic symptoms are the primary driver of agitation—always combine with an antipsychotic for definitive treatment. 2

Avoid repeated dosing without reassessment—if agitation persists after 2–3 doses, the underlying psychosis requires antipsychotic treatment rather than escalating benzodiazepine doses. 1, 3