Lorazepam — NZ Medication Guide
📋 Reviewed by a Registered Pharmacist NZ — This information is for general educational purposes only and does not replace professional medical advice. Always consult your doctor or pharmacist before starting, stopping, or changing any medication.
What is Lorazepam?
Lorazepam is an intermediate-acting benzodiazepine used for anxiety, procedural sedation, acute seizures, and alcohol withdrawal. This medication is funded by Pharmac for anxiety (oral) and acute seizures/procedural sedation (IV); Class C controlled drug.
What is Lorazepam Used For?
Lorazepam is used for short-term anxiety management, procedural sedation (pre-operative, endoscopy), acute seizure management including status epilepticus (IV), alcohol withdrawal syndrome, and acute agitation in hospital settings.
How Does Lorazepam Work?
Like other benzodiazepines, lorazepam enhances GABA-A receptor function, increasing chloride ion conductance and CNS inhibition. It has direct conjugation metabolism (via glucuronidation) — making it safer in liver impairment than many other benzodiazepines that require hepatic oxidation.
How to Take Lorazepam
For anxiety: 0.5–1 mg two to three times daily (oral). For acute seizure (hospital): 4 mg IV (may repeat once after 5–10 minutes). For procedural sedation: 1–2 mg oral or IV. Sublingual tablets provide faster onset than oral.
Common Side Effects of Lorazepam
- Sedation
- Dizziness
- Memory impairment (anterograde amnesia)
- Impaired coordination
- Weakness
Serious Side Effects — Seek Medical Attention
Contact your doctor or call 111 immediately if you experience any of the following:
- Respiratory depression (IV use — ensure resuscitation equipment available)
- Dependence and severe withdrawal syndrome
- Paradoxical agitation (particularly in elderly)
- Propylene glycol toxicity (with high-dose IV infusion — in ICU)
Drug Interactions
Lorazepam may interact with other medicines. Always inform your doctor and pharmacist of all medications you are taking. Key interactions include:
- All CNS depressants (additive sedation and respiratory depression)
- Alcohol (potentiated effect — do not combine)
- Opioids (FDA and Medsafe black box warning of fatal respiratory depression)
- Valproate (increases lorazepam levels)
New Zealand Prescribing Information
Lorazepam (1 mg tablets; 4 mg/mL IV injection — Ativan® and generics) is funded by Pharmac. It is the preferred benzodiazepine for IV treatment of status epilepticus in NZ (first-line in adults alongside midazolam buccal in the community). It is also used in ICU settings for sedation. For short-term anxiety, lorazepam should be the last resort after psychological and non-benzodiazepine options are considered.
Frequently Asked Questions
Why is lorazepam preferred for liver disease?
Most benzodiazepines (e.g., diazepam) are metabolised by liver oxidation (CYP450 enzymes), which is impaired in liver disease — causing drug accumulation. Lorazepam is conjugated by glucuronidation — a simpler liver pathway that is less affected by liver disease. This makes it safer in patients with hepatic impairment.
Is lorazepam used for seizures?
Yes — IV lorazepam is one of the first-line treatments for status epilepticus (prolonged or repeated seizures) in hospital settings. It acts quickly (within 2–5 minutes) and has a longer anticonvulsant duration than diazepam.
⚠️ Disclaimer: This page is for educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your doctor or a qualified health provider. In New Zealand, medication availability and funding may vary — check with Pharmac or your pharmacist for current information.
Reviewed by a Registered Pharmacist NZ
References & Further Information
The following New Zealand and international resources were used to inform this page: