Classifications: anxiolytic; sedative-hypnotic; benzodiazepine; Therapeutic: antianxiety; sedative-hypnotic
Pregnancy Category: D
Controlled Substance: Schedule IV
0.5 mg, 1 mg, 2 mg tablets; 2 mg/mL oral solution; 2 mg/mL, 4 mg/mL injection
Most potent of the available benzodiazepines. Effects (antianxiety, sedative, hypnotic, and skeletal muscle relaxant) are
mediated by the inhibitory neurotransmitter GABA. Action sites are thalamic, hypothalamic, and limbic levels of CNS.
Antianxiety agent that also causes mild suppression of REM sleep, while increasing total sleep time.
Management of anxiety disorders and for short-term relief of symptoms of anxiety. Also used for preanesthetic medication
to produce sedation and to reduce anxiety and recall of events related to day of surgery; for management of status epilepticus.
Chemotherapy-induced nausea and vomiting.
Known sensitivity to benzodiazepines; acute narrow-angle glaucoma; primary depressive disorders or psychosis; COPD; children
<12 y (PO preparation); coma, shock, sleep apnea; acute alcohol intoxication; dementia; pregnancy (category D), and lactation.
Renal or hepatic impairment; renal failure; organic brain syndrome; myasthenia gravis; narrow-angle glaucoma; pulmonary
disease; mania; psychosis; suicidal tendency; history of seizure disorders; GI disorders; older adult and debilitated patients;
limited pulmonary reserve.
Route & Dosage
Adult: PO 26 mg/d in divided doses (max: 10 mg/d)
Geriatric: PO 0.51 mg/d (max: 2 mg/d)
Child: PO/IV 0.05 mg/kg q48h (max: 2 mg/dose)
Adult: PO 24 mg at bedtime
Geriatric: PO 0.51 mg h.s.
Adult: IM 24 mg (0.05 mg/kg) at least 2 h before surgery IV 0.044 mg/kg up to 2 mg 1520 min before surgery
Child: PO/IV/IM 0.05 mg/kg (range: 0.020.09 mg/kg)
Adult: IV 4 mg injected slowly at 2 mg/min, may repeat dose once if inadequate response after 10 min
- Increase the evening dose when higher oral dosage is required, before increasing daytime doses.
- Injected undiluted, deep into a large muscle mass.
- IV administration to neonates, infants, children: Verify correct IV concentration and rate of infusion with physician.
- Patients >50 y may have more profound and prolonged sedation with IV lorazepam (usual max: initial dose of 2 mg).
PREPARE: Direct: Prepare lorazepam immediately before use. Dilute with an equal volume of sterile water, D5W, or NS.
ADMINISTER: Direct: Inject directly into vein or into IV infusion tubing at rate not to exceed 2 mg/min and with repeated aspiration to confirm
IV entry. Take extreme precautions to PREVENT intraarterial injection and perivascular extravasation.
INCOMPATIBILITIES Solution/additive: Dexamethasone. Y-site: Aldesleukin, aztreonam, fluconazole, foscarnet, gallium, idarubicin, imipenem/cilastatin, omeprazole, ondansetron, sargramostim, sufentanil, thiopental, TPN with albumin.
- Keep parenteral preparation in refrigerator; do not freeze.
- Do not use a discolored solution or one with a precipitate.
Adverse Effects (≥1%)Body as a Whole:
Usually disappear with continued medication or with reduced dosage. CNS:
Anterograde amnesia, drowsiness, sedation,
dizziness, weakness, unsteadiness, disorientation, depression
, sleep disturbance, restlessness, confusion, hallucinations. CV:
Hypertension or hypotension. Special Senses:
Blurred vision, diplopia
; depressed hearing. GI:
Nausea, vomiting, abdominal discomfort, anorexia.
InteractionsDrug: Alcohol, cns depressants
increases lorazepam plasma
levels, increases toxicity
; lorazepam may decrease antiparkinsonism effects of levodopa;
may increase phenytoin
levels; smoking decreases sedative and antianxiety effects. Herbal: Kava, valerian
may potentiate sedation.
Readily absorbed from GI tract. Onset:
15 min IV
; 1530 min IM. Peak:
6090 min IM; 2 h PO. Duration:
1224 h. Distribution:
Crosses placenta; distributed into breast milk. Metabolism:
Not metabolized in liver. Elimination:
In urine. Half-Life:
Assessment & Drug Effects
- Have equipment for maintaining patent airway immediately available before starting IV administration.
- IM or IV lorazepam injection of 24 mg is usually followed by a depth of drowsiness or sleepiness that permits patient
to respond to simple instructions whether patient appears to be asleep or awake.
- Supervise ambulation of older adult patients for at least 8 h after lorazepam injection to prevent falling and injury.
- Lab tests: Assess CBC and liver function tests periodically for patients on long-term therapy.
- Supervise patient who exhibits depression with anxiety closely; the possibility of suicide exists, particularly when there
is apparent improvement in mood.
Patient & Family Education
- Do not drive or engage in other hazardous activities for a least 2448 h after receiving IM injection of lorazepam.
- Do not drink large volumes of coffee. Anxiolytic effects of lorazepam can be significantly altered by caffeine.
- Do not consume alcoholic beverages for at least 2448 h after an injection and avoid when taking an oral regimen.
- Notify physician if daytime psychomotor function is impaired; a change in regimen or drug may be needed.
- Terminate regimen gradually over a period of several days. Do not stop long-term therapy abruptly; withdrawal may be induced
with feelings of panic, tonicclonic seizures, tremors, abdominal and muscle cramps, sweating, vomiting.
- Do not self-medicate with OTC drugs; seek physician guidance.
- Discuss discontinuation of drug with physician if you wish to become pregnant.