Benzodiazepines (BDZs) are used for a significant variety of conditions in the ED; their different pharmacological properties allow emergency clinicians to have a wide arsenal to treat each particular patient.
The most frequently used BZDs in the ED are lorazepam, diazepam, midazolam and clonazepam; and there is an overall deficit of comparative studies between BDZs to support one preference over another for most disorders.
In the case of lorazepam, it is the BDZ of choice (for IV use) to treat status epilepticus and seizures. For every other condition, the decision-making process of which one BDZ to use mostly depends on individual pharmacokinetic profile and its appropriateness on the desired effect.
Seizures and Status Epilepticus (SE):
IV lorazepam is superior to other IV BDZs to treat SE.
There is an established consensus of using lorazepam as the first-line IV BDZ, with a high level of evidence and recommendation for both children and adults (1, 2, 3, 5, 7, 8, 10, 11, 12, 14).
In case of unavailable IV access, midazolam 10mg IM is preferred because it is at least comparable in efficacy to IV lorazepam and is easier to administer (1, 9, 11, 13). In the case of unavailable midazolam, lorazepam is a good alternative for IM route as it has good bioavailability as well. Do not administer diazepam by IM route because of its erratic response (13).
Anxiety disorders, acute anxiety states:
Benzodiazepines have a dominant role for short-term, acute management of anxiety disorders in the ED (3). Amongst them, lorazepam is a good alternative between other BDZ for the management of anxiety disorders in the ED, considering its rapid onset of action and long lasting effect.
Lorazepam is indicated as an adjunctive or single medication to treat undifferentiated agitation in the ED.
Some clinicians consider lorazepam as a first-line medication, usually combined with a first generation (typical) antipsychotic such as haloperidol (3).
Studies have shown lorazepam to have a similar efficacy compared with haloperidol but inferior to the combination of both (15, 21).
It can be administered with haloperidol in the same syringe, a feature that could be useful in the ED compared with other BDZ (20).
Midazolam (IM) is another validated BDZ to treat agitation.
This wide spectrum of conditions can be divided into (i) pathological sympathetic stimulation (eg. thyroid storm, tetanus disease, pain, etc), (ii) exogenous sympathomimetic toxicity and (iii) substance withdrawal response. Caution should be taken as these condition’s syndromic presentations can frequently overlap with undifferentiated agitation, and many of them have serious short-term morbidity and mortality.
Benzodiazepines are part of the standard therapy for acute cocaine intoxication (22, 23, 25). Diazepam and lorazepam are the most studied BDZ for cocaine-associated chest pain, and both are considered as first-line alternatives (3, 4, 25).
For Alcohol Withdrawal Syndrome lorazepam and diazepam are considered the best alternatives (3), but most authors recommend escalating doses of diazepam as the BDZ of choice (4, 24).