What is the long-acting version of Ativan (lorazepam)?

Clonazepam is the Long-Acting Version of Ativan (Lorazepam)

Clonazepam is the long-acting benzodiazepine alternative to Ativan (lorazepam), with an elimination half-life of 30-40 hours compared to lorazepam's shorter duration of action. 1

Pharmacokinetic Comparison

Lorazepam (Ativan) is considered a short-to-intermediate acting benzodiazepine, while clonazepam is classified as a long-acting benzodiazepine:

• Lorazepam (Ativan)

  • Intermediate-acting benzodiazepine
  • Used primarily for short-term management of anxiety and insomnia
  • Preferred in elderly patients or those with hepatic dysfunction due to its shorter duration of action 1

• Clonazepam

  • Long-acting benzodiazepine with elimination half-life of 30-40 hours
  • Rapidly absorbed after oral administration with 90% bioavailability
  • Maximum plasma concentrations reached within 1-4 hours
  • Recommended dosage range: 0.25-2.0 mg 1

Clinical Applications of Clonazepam as a Long-Acting Alternative

Clonazepam is often selected when a longer duration of action is needed. It has several applications where its long-acting properties are beneficial:

• REM Sleep Behavior Disorder (RBD)

  • First-line treatment for RBD with strong evidence support (Level B recommendation) 1
  • Effective for controlling vigorous/violent behaviors and vocalizations during sleep
  • Most patients respond well to low doses (0.25-1.0 mg) at bedtime 1

• Seizure Management

  • Effective for long-term seizure prophylaxis in refractory epilepsy
  • Has a duration of action of approximately 24 hours, compared to lorazepam's effect of up to 72 hours in seizure control 2

• Chronic Anxiety Disorders

  • Long-acting benzodiazepines like clonazepam are preferred for sustained levels of anxiety
  • While lorazepam is better suited for episodic anxiety 3

Important Clinical Considerations

When choosing between lorazepam and clonazepam, several factors should be considered:

• Side Effect Profile

  • Clonazepam can cause sedation (particularly morning sedation), impotence, early morning motor incoordination, confusion, and memory dysfunction 1
  • Risk of worsening sleep apnea at doses of 0.5-1.0 mg
  • Risk of confusion and falls at higher doses (2.0 mg) 1

• Special Populations

  • Use clonazepam with caution in patients with:
    • Neurodegenerative disorders
    • Obstructive sleep apnea
    • Underlying liver disease 1
    • Elderly patients (increased sensitivity to benzodiazepine effects) 1

• Tolerance and Dependence

  • Studies report minimal dosage tolerance with clonazepam
  • Dose escalation is reportedly rare
  • Withdrawal symptoms typically do not develop upon dose reduction or discontinuation 1

Practical Prescribing Guidelines

When prescribing clonazepam as a long-acting alternative to lorazepam:

1. Start with low doses: 0.25-0.5 mg at bedtime
2. Titrate gradually: Increase by 0.25-0.5 mg increments as needed
3. Monitor for side effects: Particularly morning sedation, confusion, and falls
4. Consider gender differences: Some studies report women may require higher dosing (1.4 ± 0.4 mg) than men (0.68 ± 0.4 mg) 1
5. Avoid abrupt discontinuation: Although withdrawal symptoms are less common than with other benzodiazepines, gradual tapering is still recommended

Remember that while clonazepam is the long-acting alternative to lorazepam, the choice between these medications should be based on the specific clinical scenario, with consideration of the patient's age, comorbidities, and the intended duration of treatment.