Diazepam is a long-acting benzodiazepine that enhances GABA-A receptor activity at the benzodiazepine binding site, increasing chloride conductance and producing CNS depression. Active metabolites (nordazepam, oxazepam, temazepam) extend the effective duration far beyond the parent drug's plasma half-life. Effects include sedation, anxiolysis, anterograde amnesia, anticonvulsant activity, and muscle relaxation. Highly lipid-soluble; rapid CNS entry but also rapid redistribution to peripheral tissues, which is why a single IV dose has relatively short clinical effect despite the long half-life.

• Status epilepticus and acute seizure termination
• Alcohol withdrawal (cornerstone of CIWA-guided treatment)
• Severe muscle spasm and tetanus
• Organophosphate poisoning (seizures and muscle fasciculations - adjunct to atropine and 2-PAM)
• Severe sympathomimetic toxicity (cocaine, methamphetamine, MDMA) - first-line for agitation and hyperthermia control
• Anxiety (short-term, limited operational role)

• Known hypersensitivity to diazepam or benzodiazepines
• Acute narrow-angle glaucoma
• Severe respiratory depression (relative; depends on clinical context)
• Sleep apnea (severe untreated)
• Severe hepatic impairment

Common: respiratory depression, sedation, hypotension, amnesia (anterograde), ataxia. Tolerance and dependence with chronic use; severe withdrawal syndrome possible after prolonged use (seizures, autonomic instability, can be fatal). Long active metabolite half-life means cumulative effects with repeated dosing - this is the main operational distinguisher from midazolam. IV vehicle contains propylene glycol; large doses or prolonged infusion can cause propylene glycol toxicity (lactic acidosis, hyperosmolality, renal failure). IV administration is associated with thrombophlebitis and venous irritation due to the propylene glycol vehicle. Drug interactions: additive respiratory depression with opioids; CYP3A4 inhibitors increase levels; alcohol potentiates depression; smoking induces metabolism (lower levels). Half-life 20 to 50 hours (parent); nordazepam metabolite 30 to 200 hours. Pregnancy Category D. Passes into breast milk; may cause infant sedation and feeding difficulty. Reversal: flumazenil. Schedule IV controlled substance.

Seizure: 0.2 to 0.5 mg/kg IV (max 10 mg per dose), repeat every 5 to 10 minutes. Rectal Diastat: 0.5 mg/kg PR for age 2 to 5 years; 0.3 mg/kg for 6 to 11 years; 0.2 mg/kg for 12 years and older.

Peak Effect: IV: 5 minutes (initial), then redistribution. PO: 30 minutes to 2 hours.

Duration: 30 minutes to 4 hours (single IV dose due to redistribution). Cumulative effect with repeated dosing.

Schedule IV controlled substance - secured storage, chain of custody documentation, administration and waste log. Store at room temperature (15 to 30 degrees C). Protect from light. IV solution: do not refrigerate. Solution is light-yellow tinted at baseline; discard if significantly discolored or contains particulate matter.

Reconstitution:

Available as 5 mg/mL injectable. IV: give undiluted slow push at 5 mg per minute through a large vein with running IV fluid. Do not dilute (precipitates in most IV fluids). Rectal Diastat: pre-filled rectal gel applicator. Valtoco intranasal: pre-filled IN spray device (5, 10, 15, or 20 mg per device).

Diazepam is not the TCCC first-line benzodiazepine - midazolam holds that position due to faster IM/IN onset and more reliable absorption. Diazepam appears in TEMS supplemental formularies, alcohol withdrawal protocols, and toxicology kits. Specific tactical relevance: organophosphate (nerve agent) exposure where diazepam IV is the doctrine anticonvulsant adjunct to atropine and 2-PAM; severe sympathomimetic intoxication where the long duration is operationally useful for sustained sedation. By definition the patient is non-mission-capable once requiring diazepam.