Pharmacology and Medication Safety
Core concepts
Prehospital pharmacology requires understanding indications, contraindications, doses, routes, onset, adverse effects, and drug interactions. High-alert medications include vasopressors, insulin, opioids, sedation agents, antiarrhythmics, and concentrated electrolytes. Weight-based pediatric dosing and infusion calculations are common test areas. Know how to prepare push-dose pressors and infusions safely, verify concentrations, and label all syringes. Medication safety depends on the rights of administration, independent double-checks when feasible, and documentation.
Traps
Common traps include confusing epinephrine concentrations, giving amiodarone too rapidly, and using flumazenil in mixed overdose or seizure-prone patients. Naloxone can precipitate withdrawal and agitation. Vasopressors can cause extravasation injury. Do not assume a medication is compatible with the same line without checking. Pediatric doses are especially error-prone.
Rule of thumb
When calculating a dose, estimate the expected volume and compare it with the syringe size. If the volume seems implausible, stop and recalculate. Label every medication and confirm the concentration aloud.
Worked example
A patient needs a push-dose vasopressor. Confirm the concentration, draw up the correct volume, label the syringe, and give in small titrated increments while monitoring blood pressure and heart rate. The trap is using a concentrated vial without diluting or mislabeling the syringe.