Mechanism of Action

Enhance the effect of GABA at the GABA-A receptor by increasing the FREQUENCY of chloride channel opening (barbiturates increase duration — a classic NCLEX distinction). More chloride influx hyperpolarizes the neuron, making it harder to fire — producing sedation, anxiolysis, muscle relaxation, and anticonvulsant effects. They require endogenous GABA to already be present rather than opening the channel directly, which underlies their relative safety versus barbiturates. Duration of action drives selection: short-acting (midazolam) for procedures, intermediate (lorazepam) for seizures/withdrawal, long-acting (diazepam, clonazepam) for sustained coverage.

Common Medications

lorazepamPrototype

preferred in liver impairment — conjugated, no active metabolites; IV first-line for status epilepticus

diazepam

long-acting; active metabolites; problematic in hepatic dysfunction

midazolam

short-acting; procedural sedation

alprazolam

clonazepam

long-acting

chlordiazepoxide

alcohol withdrawal

Indications

generalized anxiety disorder

short-term only; SSRIs first-line for chronic anxiety

acute panic attack

alcohol withdrawal

chlordiazepoxide, lorazepam; cross-tolerance at GABA receptors

status epilepticus

IV lorazepam is first-line

procedural sedation

midazolam

preoperative anxiolysis

Side Effects

sedation

expected at therapeutic dose

dizziness

ataxia

cognitive impairment

anterograde amnesia

midazolam — client cannot retain teaching during amnestic window

fall risk in older adults

sedation + impaired coordination

Contraindications & Interactions

Interactions

concurrent opioids

FDA boxed warning — additive respiratory depression/sedation

alcohol

additive CNS/respiratory depression

other CNS depressants

Contraindications

benzodiazepine dependence

contraindication to reflexive flumazenil — precipitates withdrawal seizures

concurrent seizure disorder

flumazenil can trigger seizures

Administration & Monitoring

monitor respiratory rate

priority assessment; support airway if RR low

monitor oxygen saturation

monitor level of sedation/arousability

assess fall risk in older adults

assess duration and frequency of use before flumazenil

chronic use is the key contraindication to reversal

flumazenil is the reversal agent

IV; NOT given reflexively — seizure risk in dependence

taper rather than stop abruptlyHold

reduce gradually over weeks after ~2–4 weeks of daily use

confirm discharge teaching with a companion

midazolam amnesia — client teach-back unreliable

Patient Teaching

do not stop abruptly

withdrawal seizures; provider-guided taper only

avoid alcohol

do not drive until sedation effects are known

never share the medication

rise slowly and prevent falls

report excessive drowsiness or slowed breathing

expect short-term use

dependence develops within 2–4 weeks

Report Nowescalate immediately

respiratory depression HallmarkBlack Box

FDA boxed warning — life-threatening, especially combined with opioids or alcohol; support airway/oxygen FIRST (ABCs before flumazenil)

withdrawal seizures

abrupt discontinuation after weeks of daily use; tonic-clonic, can be fatal — taper mandatory

paradoxical agitation

agitation/combativeness/confusion after a dose, especially older adults; reevaluate medication

oversedation

difficult to arouse; treat as airway threat

Clinical Pearl

Frequency, not force — benzos make GABA open the chloride gate more often, not longer (that's barbiturates). And benzo withdrawal can kill; opioid withdrawal feels like death but rarely is. If they've taken it daily for weeks, taper — never stop cold.