Ativan is the brand name for lorazepam, an intermediate-acting benzodiazepine FDA-approved for anxiety disorders and used widely in emergency medicine for acute agitation, alcohol withdrawal, and status epilepticus. Onset is 20 to 40 minutes orally, with a half-life of about 10 to 20 hours. It carries the full benzodiazepine class risks: dependence within weeks of regular use, severe withdrawal, and fatal respiratory depression when combined with opioids or alcohol.
What Ativan is
Ativan is the brand name for lorazepam, a medication in the benzodiazepine class. It enhances the effect of GABA at GABA-A receptors. It was approved by the FDA in 1977 and is widely used in both outpatient and inpatient settings. Generic lorazepam is widely available. The MedlinePlus drug information page for lorazepam covers consumer-facing essentials.
A distinctive feature of lorazepam is its pharmacokinetics: it has no active metabolites and is conjugated rather than oxidized by the liver. That makes it the benzodiazepine of choice in patients with significant liver disease and in many older adults, where oxidative metabolism is reduced. It's also available in injectable form, which is why it's the typical first-line benzodiazepine in emergency medicine.
What it does
Lorazepam enhances GABA at GABA-A receptors throughout the central nervous system. The acute effects are reduced anxiety, muscle relaxation, mild sedation, and (at higher doses) impaired memory and motor coordination. Onset after an oral dose is 20 to 40 minutes; the half-life is 10 to 20 hours, intermediate between alprazolam and clonazepam.
The mechanism is identical to other benzodiazepines. The differences across the class are in onset, duration, metabolism, and route options, not in the underlying receptor effect.
What it feels like
Patients describe a felt calming within 30 minutes or so after an oral dose, with effect persisting for several hours. Muscle tension softens. The acute calming arc is similar to alprazolam, slightly slower in onset, with a longer felt effect.
Sedation, particularly in the first doses, is common. The cognitive effects (slowed thinking, mild memory impairment) are dose-related and often underestimated by patients who feel them as helpful relief.
When it's chosen
In clinical practice, lorazepam is often chosen for:
- Patients with significant liver disease, where its conjugative metabolism is safer than the oxidative metabolism of other benzodiazepines
- Older adults when a benzodiazepine is judged necessary, again because of the metabolism profile
- Emergency settings: acute agitation, severe anxiety crises, alcohol withdrawal management, status epilepticus
- Procedural anxiety (MRI, dental procedures) when a slightly longer-lasting agent than alprazolam is appropriate
- Short-term bridging while an SSRI takes effect
For sustained outpatient treatment of generalized anxiety or panic disorder, the same caveats apply as with other benzodiazepines: SSRIs, SNRIs, and CBT are first-line per the NIMH anxiety disorders overview, and lorazepam is best reserved for narrow short-term use.
Typical dosing and timeline
Starting dose for anxiety is typically 0.5 to 1 mg two or three times daily. The typical effective dose range is 1 to 6 mg daily in divided doses. For short-term bridging while an SSRI takes effect, two to four weeks of intermittent use is a typical pattern.
Lorazepam is also available sublingually and as an injection. The sublingual form is sometimes used in panic crisis management, though its abuse potential is similar to oral.
Side effects and cautions
Sedation, slowed cognition, impaired motor coordination, and falls are the most common adverse effects, with older adults at particular risk. Benzodiazepines, including lorazepam, are on the American Geriatrics Society Beers Criteria as medications to avoid in older adults except in narrow situations.
The FDA boxed warning applies to lorazepam as to other benzodiazepines: concomitant use with opioids increases the risk of fatal respiratory depression; physical dependence develops within weeks of regular use; abrupt discontinuation can produce severe withdrawal including seizures. Alcohol potentiates all of these risks. The NIMH overview of mental health medications addresses the class.
What Ativan doesn't do
Ativan doesn't treat the underlying anxiety disorder. The acute effect is symptomatic relief. When the dose effect wanes, the underlying pattern is unchanged.
Ativan doesn't address the cognitive and behavioral patterns of anxiety. For sustained improvement in panic disorder, exposure therapy and an SSRI produce more durable results than any benzodiazepine alone.
Ativan isn't appropriate as monotherapy for chronic anxiety in most patients. The class-level case for non-benzodiazepine first-line treatment is detailed in Benzodiazepine vs SSRI for panic.
Comparison with related medications
Compared with alprazolam, lorazepam has a slightly slower onset and longer felt duration, with less prominent inter-dose rebound. Compared with clonazepam, lorazepam has a shorter half-life and no active metabolites, which makes it preferred in liver disease and older adults but produces more pronounced inter-dose effects when taken less than three times daily. The full class context is in Benzodiazepines for anxiety.