Lorazepam
Lorazepam
CLINICAL USE
Benzodiazepine:Short-term use in anxiety or insomnia Status epilepticus Perioperative
DOSE IN NORMAL RENAL FUNCTION
Anxiety: 1–4 mg daily in divided doses Insomnia associated with anxiety: 1–2 mg at bedtimeAcute panic attacks: (IV/IM): 25–30 mcg/ kg; repeat 6 hourly if required; usual range 1.5–2.5 mgStatus epilepticus: 4 mg IV repeated once after 10 minutes
PHARMACOKINETICS
Molecular weight                           :321.2 %Protein binding                           :85 %Excreted unchanged in urine     : <1 Volume of distribution (L/kg)       :0.9–1.3half-life – normal/ESRD (hrs)      : 10 to 20 /32–70
DOSE IN RENAL IMPAIRMENT
GFR (mL/MIN)
20 to 50     : Dose as in normal renal function 10 to 20     : Dose as in normal renal function <10           : Dose as in normal renal function DOSE IN PATIENTS UNDERGOING RENAL REPLACEMENT THERAPIES
CAPD                :Unlikely dialysability. Dose as in normal renal function. HD                     :Not dialysed. Dose as in normal renal functionHDF/high flux   :Unknown dialysability. Dose as in normal renal function CAV/VVHD      :Not dialysed. Dose as in normal renal function IMPORTANT DRUG INTERACTIONS
Potentially hazardous interactions with other drugsAntibacterials: metabolism possibly increased by rifampicinAntipsychotics: increased sedative effects; increased risk of hypotension, bradycardia and respiratory depression when parenteral benzodiazepines are given with IM olanzapineAntivirals: concentration possibly increased by ritonavirDisulfiram: metabolism inhibited, increased sedative effectsSodium oxybate: enhanced effects of sodium oxybate – avoid Ulcer-healing drugs: metabolism inhibited by cimetidine ADMINISTRATION
Reconstition
Route
Oral, IV, IM, sublingual Rate of Administration
Slow IV bolus Comments
Onset of effect after IM injection is similar to oral administrationIV route preferred over IM route Dilute 1:1 with sodium chloride 0.9% or water for injectionCan be used undiluted. (UK Critical Care Group, Minimum Infusion Volumes for fluid restricted critically ill patients, 3rd Edition, 2006) OTHER INFORMATION
Patients with impaired renal or hepatic function should be monitored frequently and have their dosage adjusted carefully according to response. Lower doses may be sufficient in these patientsLorazepam as intact drug is not removed by dialysis. The glucuronide metabolite is highly dialysable, but is pharmacologically inactiveIncreased CNS sensitivity in patients with renal impairment.
See how to identify renal failure stages according to GFR calculation
See how to diagnose irreversible renal disease
Home