- 600mg effervescent tablets and oral capsules (PO)

- 6gr/60ml (100mg/ml) solution vial (PO)

- 6gr/30ml (200mg/ml) injection vial (IV)

Executive Summary
N-Acetylcisteine (NAC) is a mucolytic, antioxidant and a glutathione-inducer. It is positioned as the cornerstone antidote for the prevention and treatment of liver toxicity secondary to acetaminophen (APAP) overdose, with US-FDA approval for IV, PO and effervescent tablets administration.

Adult and Pediatric dose for acetaminophen overdose: oral administration, 18 doses total. 

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50mg lyophilized powder (IV)

Executive Summary
Alteplase, a fibrin-specific Tissue Plasminogen Activator (fibrinolytic) is widely accepted for emergency revascularization in acute myocardial infarction (MI),  high risk acute pulmonary embolism (PE), and acute ischemic stroke (AIS). In emergency medicine it is also used in  intermediate-high risk PE and cardiac arrest when there is a high suspicion of MI or PE as the cause, in both scenarios the decision should be taken cautiously and in very selected cases.

Always seriously consider the contraindications and balance the risk of intracranial and other major bleeding events versus the benefit of the therapy. Fibrinolysis is an intervention that should be decided -or at least supported- by a specialist (emergency medicine, neurologist, cardiologist, intensivist).

Dosing Summary

Acute Coronary Syndrome with ST elevation (<12 hours)

FDA approved. 

Adult dose:


Acute Ischemic Stroke (<4.5 hours)

FDA approved for <3 hours after symptom onset (1996), Universally accepted use in <4.5 hours.
Adult dose:


Pulmonary Embolism

FDA approved. 

Adult dose

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- 5, 7.5 and 10mg tablets (PO, immediate release)
- 10, 15 and 30mg tablets (PO, extended release)

Executive Summary
Ciclobenzaprine is a centrally acting skeletal muscle relaxant widely prescribed to relieve acute painful musculoskeletal conditions as an adjunct treatment to physical therapy  and rest. It is also used as a temporary adjuvant medication along with non-steroidal anti-inflammatory drugs (NSAIDs) or acetaminophen. 


Adult dose for acute painful musculoskeletal spasms

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5mg/2ml ampoules (IV, IM)

Executive Summary

Droperidol is a first generation antipsychotic (so-called typical antipsychotics, same class as haloperidol) that acts as a D2 dopamine receptor antagonist. Droperidol also has some histamine and serotonin antagonist properties. 


Adult dose for undifferentiated agitation in the ED

5-10mg IM

Adult dose for migraine, acute vertigo, nausea or vomiting and cannabinoid hyperemesis

1.25-2.5mg IV or IM

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20mg/10ml ampoules (IV)

Executive Summary
Etomidate is an ultra-ultrashort-acting, non-barbiturate hypnotic intravenous anesthetic agent. Is one of the most used and preferred hypnotic agents in the ED for Rapid Sequence Intubation. 


Pharmacology for a single bolus administration:


Adult dose for rapid sequence intubation:  

0.3mg/kg IV (total body weight).

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1mg/1ml ampoules (IV, IM, IO, nebulization, subcutaneous)

Executive Summary

Epinephrine is an endogenous catecholamine non-selective agonist of all adrenergic receptors with a major role in emergency medicine on a variety of different diagnoses. 


*ROSC: Return of Spontaneous Circulation

Adult dose for anaphylaxis
0.01mg/kg (max 0.5mg per dose) IM into the anterolateral aspect of the thigh.


Adult dose for cardiac arrest
1mg every 3 to 5 minutes IV or IO

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Hypertonic saline
3%, 10% and 23.4%, 100ml ampoules (IV)

Executive Summary

Hypertonic saline solutions (HTS) are electrolyte concentrates of NaCl (over 0.9%) and  considered to be high alert medications that are cautiously used to treat symptomatic hyponatremia and acute intracranial hypertension (IH) secondary to multiple causes, but mainly to traumatic brain injury. 

Adult dose for acute intracranial hypertension caused by TBI

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- 4mg/2ml, 4mg/1ml and 2mg/1ml ampoules (IV, IM)

- 0,5mg, 1mg and 2mg tablets (PO, sublingual)

Executive Summary
Lorazepam is an intermediate acting benzodiazepine (BDZ) –a GABA receptor enhancer– with CNS depressant effects including sedative, hypnotic, skeletal muscle relaxing and anticonvulsant activity. It can be administered either by intravenous, intramuscular, sublingual or oral routes. Along with midazolam and clonazepam, lorazepam is one of the most frequently indicated BDZs in the ED. 

Sedation timing with single 2-4mg dose:

Onset (IV): 5-10 minutes*

Peak Effect (IV): 30 minutes

Duration (IV): 2-6 hours

(*shorter to terminate seizures)

Onset (IM) 15 minutes

Peak Effect (IM) 60 minutes

Duration (IM) 6-8 hours

Adult dose for status epilepticus:
0.1mg/kg IV (max 4mg/dose).

Adult dose for undifferentiated agitation:
2-4mg sublingual, IV or IM as needed (if severely agitated, IM route is prefered).

Acute anxiety disorder:

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Levetiracetam #latest_upload

- 500mg/5ml vial (IV)

- 500mg tablets (PO) and 100mg/ml oral solution (PO)

Executive Summary

Levetiracetam (LEV) is a second generation antiepileptic drug (AED) that has gained popularity in the ED for the treatment of status epilepticus (with a conjunction of benzodiazepines, usually IV lorazepam or IM midazolam); 

Adult dose for status epilepticus

Loading dose of 60mg/kg IV (max 4,500mg) in 15 minutes. 

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4mg/4ml ampoules (IV)

Executive Summary
Norepinephrine (NE) is used for hemodynamic support frequently as a first-line vasopressor with the exception of anaphylaxis (epinephrine) and post cardiac arrest care (epinephrine). Consider using noradrenaline in combination with inodilator drugs in cardiogenic shock. 

Adult dose for shock:
0.01-0.3 ug/kg/min IV

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- 5mg and 10mg tablets (sublingual)
- 10mg lyophilized powder (IM)

Executive Summary
Olanzapine is a second generation (atypical) antipsychotic with a potent antagonism of serotonin 5-HT2A, 5-HT2C, dopamine D1-4, histamine H1 and alpha1-adrenergic receptors. It also has a moderate antagonism of muscarinic M1-5 receptors, as well as a  weak agonism to GABA-A, BZD and beta-adrenergic receptors. 


In the ED, olanzapine  is frequently indicated as a first-line antipsychotic for acute agitation associated with psychiatric disorders (US FDA and EMA approved for agitation in individuals with schizophrenia and bipolar disorder). Agitation in the ED is a very complex situation that includes a variety of dissimilar scenarios with a wide range of therapeutic options. Many clinical guidelines have been proposed with substantial differences between them; as emergency physicians, it is of great importance to be familiarized with the available therapeutic arsenal for agitation, such as haloperidol, droperidol, benzodiazepines, propofol, ketamine, etc. 

Adult dose for severe agitation:
5 to 10mg IM, repeated every 20 min if necessary, with a maximum of 30mg/day for intramuscular administration. 

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Phentolamine (for extravasated vasopressors)

- 10mg/1ml vials (subcutaneous)
- 5mg lyophilized powder (subcutaneous)

Executive Summary
Phentolamine is a vasodilator used to prevent tissue necrosis caused by extravasated catecholamine infusions (epinephrine, norepinephrine, dopamine, etc). Available in the US. Limited stock in Canada. Unavailable in Chile. 

Adult dose for vasopressor extravasation:
5-10mg diluted in 10-20ml of NaCl 0.9% subcutaneous immediately after extravasation (use within 12 hours). 

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Rabies Vaccine

Single-dose 1ml and 0,5ml vials, both equivalent to 1 vaccination dose (IM)

Executive Summary
Rabies is a zoonotic disease positioned as one of the most lethal viral infections; mortality approaches 100%. It is also preventable in nearly 100% of expositions when vaccination has been properly administered. 

Adult and pediatric vaccination regimen for post-exposure prophylaxis (PEP)


*Some regions and their local guidelines still  recommend a universal 5-dose regimen for PEP as previously was recommended by the US-CDC, and currently some manufacturers. 

**Complete 4 doses of PEP scheme or 3 doses of PrEP (pre-exposure prophylaxis).

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50mg lyophilized powder (IV)

Executive Summary

Acute Myocardial Infarction with ST elevation (STEMI <12hrs)

FDA approved, 2000. Indicated when anticipated STEMI diagnosis to Percutaneous Coronary Intervention-mediated reperfusion time is >120min. 

Adult dose (IV ,bolus):


Acute Ischemic Stroke (AIS <4.5hrs)

Not FDA approved. 

Adult dose (IV ,bolus):


Pulmonary Embolism (PE)

Not FDA approved. Prefer alteplase for PE fibrinolytic therapy. If unavailable, consider tenecteplase.

Adult dose (IV, bolus):

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Tetanus Immune Globulin

250 unit prefilled syringes (IM)

Executive Summary
Tetanus Immune Globulin (TIG) is indicated for tetanus disease treatment and prophylaxis (the latter in individuals without updated or an  unknown tetanus immunization who have suffered a contaminated or a  tetanus-prone wound).

Adult dose for tetanus treatment and prophylaxis

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Thiamine (Vitamin B1)

- 30mg/ml and 200mg/2ml vials (IV, IM)

- 10, 50, 100 and 250mg tablets (PO)

Executive Summary
Thiamine (vitamin B1) is a water-soluble vitamin that is essential in the creation and utilization of cellular energy  related to aerobic glycolysis in the citric acid cycle. Its deficiency leads to cardiovascular (heart failure) and neurologic disease (Wernicke - Korsakoff syndrome, "WK"). In the ED thiamine is frequently indicated in the prevention and treatment of WK, mainly in patients with ethanol dependence and/or malnutrition. 


Adult dose for WK prevention and treatment

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Tranexamic Acid (TXA)

1000mg/10ml ampoules (IV)

Executive Summary

The antifibrinolytic agent tranexamic acid (TXA) is a synthetic lysin derivative that binds plasminogen and plasmin, blocking their interaction with fibrin. It is indicated extensively in the ED for a variety of bleeding scenarios. 


Adult dose for trauma with risk of significant hemorrhage

1gr in 10 min IV + 1gr in 8 hrs IV.

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Comments and abbreviations

TBW Total body weight
IBW Ideal body weight
NMDA N-methyl-D-aspartate (receptor)
RSI Rapid Sequence Intubation



AIS Acute ischemic stroke

U.S. FDA Food and Drug Administration

MI Myocardial infarction

PE Pulmonary embolism

ROSC Return of spontaneous circulation



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