EMT formulary

The seven drugs, and what stops you giving them.

An EMT carries a very short formulary. Knowing it cold is cheap marks on the exam and the difference between helping and harming on the truck. The contraindications matter more than the indications — the exam tests what stops you, not what starts you.

Scope varies. Which of these you may give, which you may only assist a patient with, and which need online medical direction, is set by your state and your medical director — not by this page. Where a drug is commonly “assisted” rather than administered, it is marked. Doses are the usual adult figures taught to the national standard; your protocol is the authority.

Oxygen

O₂ · gas, inhaled
Indications
Hypoxia (SpO₂ under 94% on room air), respiratory distress, shock, suspected carbon monoxide poisoning, and cardiac arrest.
Contraindications
None in a hypoxic patient. There is no patient you may leave hypoxic.
Dose & route
Titrate to 94–98%
Nasal cannula 1–6 L/min · non-rebreather 10–15 L/min · BVM with reservoir at 15 L/min. In suspected CO poisoning, high-flow regardless of the reading — the pulse oximeter cannot tell carboxyhemoglobin from oxyhemoglobin and reads falsely high.
Action
Raises the fraction of inspired oxygen, correcting hypoxia at the tissue.
Side effects
Dries and irritates mucosa. Excess oxygen is itself harmful after cardiac arrest, in stroke and in myocardial infarction, which is why the target is a window and not a maximum.
Before you give itMatch the device to the need. A comfortable patient at 88% needs a cannula titrated up, not a non-rebreather. A patient who is not moving enough air needs a BVM, and no mask fixes inadequate ventilation.

Aspirin

acetylsalicylic acid · chewable tablet, oral
Indications
Chest pain or discomfort of suspected cardiac origin.
Contraindications
  • Known aspirin allergy
  • Active gastrointestinal bleeding or known bleeding disorder
  • Unable to swallow or to protect their own airway
  • A child or adolescent — risk of Reye’s syndrome
Dose & route
160–324 mg, chewed
Usually four 81 mg chewable tablets. Chewed, not swallowed whole — chewing gets it absorbed in minutes rather than tens of minutes, and minutes are what this drug is for.
Action
Irreversibly blocks platelet aggregation, so the clot that is forming stops growing. It does not dissolve the clot already there and it does not treat the pain.
Side effects
Gastric irritation, nausea, prolonged bleeding.
Before you give itAsk whether they have already taken any today, and how much. A patient on a daily 81 mg still gets the full dose — a maintenance dose is not a treatment dose.

Oral glucose

dextrose gel · buccal
Indications
Suspected hypoglycemia — altered mental status in a diabetic patient, or a measured glucose below about 70 mg/dL — in a patient who can still swallow and protect their airway.
Contraindications
  • Unresponsive, or unable to swallow
  • No gag reflex
Dose & route
One tube, 15–24 g
Squeezed between the cheek and the gum, a little at a time, with the patient sitting up.
Action
Absorbed across the buccal mucosa and swallowed, raising blood glucose.
Side effects
Almost none. The danger is not the drug, it is aspiration.
Before you give itAsk them to swallow on command and watch them do it. “They’re awake enough” is not the test. And ask which diabetes medication they take: a long-acting sulfonylurea will outlast the gel by hours, which is why that patient needs transport even after they wake up and feel fine.

Epinephrine

adrenaline · auto-injector, intramuscular
Often assisted — check your scope
Indications
Anaphylaxis: a likely allergen plus more than one body system involved, or hypotension after a known allergen. Skin findings alone are an allergic reaction, not anaphylaxis.
Contraindications
None in true anaphylaxis. Age, heart disease and hypertension are cautions to be aware of, not reasons to withhold it from someone whose airway is closing.
Dose & route
Adult 0.3 mg IM · Child 0.15 mg IM
Into the lateral thigh, through clothing if necessary, held in place for the time the device specifies. The paediatric dose is usually for a child under about 30 kg (66 lb). May be repeated in 5–15 minutes per protocol if there is no improvement.
Action
Alpha-1 vasoconstriction raises blood pressure and reduces airway swelling; beta-1 increases heart rate and force; beta-2 opens the bronchioles. It is the only drug that addresses all three.
Side effects
Tachycardia, palpitations, tremor, anxiety, headache, pallor. All expected, none a reason to have withheld it.
Before you give itLateral thigh, never the buttock and never a digit. Then transport — a biphasic reaction can return hours later, so this patient goes to hospital even if they recover completely in front of you.

Naloxone

Narcan · intranasal or intramuscular
Indications
Suspected opioid overdose with respiratory depression. The indication is the breathing, not the drug use.
Contraindications
Known hypersensitivity. That is all.
Dose & route
4 mg intranasal, or 0.4–2 mg IM
Intranasal is one device into one nostril; repeat in the other nostril after 2–3 minutes if there is no response. Doses vary by product and protocol.
Action
Competes opioids off their receptors, reversing the respiratory depression.
Side effects
Acute withdrawal: vomiting, agitation, combativeness, sometimes seizure. Plan for a patient who wakes up frightened and angry, and protect the airway from the vomit.
Before you give itVentilate first. Opioid overdose kills by hypoxia, and a bag-valve mask treats that immediately while naloxone takes minutes. Naloxone also wears off sooner than many opioids, so a patient who wakes up can go back down — they are still going to hospital.

Albuterol

salbutamol · nebulizer or metered-dose inhaler
Often assisted — check your scope
Indications
Bronchospasm with wheezing — asthma, COPD, and some allergic reactions.
Contraindications
  • Known hypersensitivity
  • Not prescribed to this patient, where your protocol requires it to be
  • Unable to follow the instructions to use the device, for an MDI
Dose & route
2.5 mg in 3 mL saline, nebulized
Or 2 puffs by metered-dose inhaler, ideally through a spacer. Nebulized over about 5–15 minutes, driven by oxygen.
Action
A beta-2 agonist: relaxes bronchial smooth muscle and opens the airway. It does nothing for the swelling and mucus underneath, which is why a severe asthmatic still deteriorates.
Side effects
Tachycardia, tremor, nervousness, palpitations.
Before you give itListen before and after, and count a pulse before you start. A chest that goes quiet after treatment has either opened up or stopped moving air — and the difference is the patient’s work of breathing and mental status, not the wheeze.

Nitroglycerin

glyceryl trinitrate · sublingual tablet or spray
Usually assisted — the patient’s own prescription
Indications
Chest pain of suspected cardiac origin, in a patient with their own prescribed nitroglycerin.
Contraindications
  • Systolic blood pressure below 100 mmHg (some protocols say 90 — know yours)
  • A sildenafil-type drug in the last 24–48 hours — ask every patient, not only the men
  • Maximum dose already taken — usually three
  • Suspected head injury
  • Heart rate under 50 or over 100
Dose & route
0.4 mg sublingual, up to 3 doses
One tablet or spray under the tongue, repeated every 5 minutes, with a blood pressure before every dose.
Action
Dilates veins, dropping preload and so the work the heart has to do. It also dilates the coronary arteries.
Side effects
Hypotension, throbbing headache, dizziness, reflex tachycardia.
Before you give itA blood pressure before every single dose, not just the first. An inferior MI may involve the right ventricle, which depends on exactly the preload this drug removes — those patients can drop their pressure catastrophically on a normal dose.