Pharmacology and Safe Medication Administration in Midwifery
Core concepts
Know the rights of medication administration: right client, drug, dose, route, time, and documentation (plus reason and response). Understand pharmacokinetics in pregnancy - increased plasma volume and renal clearance can alter drug levels - and the principles of safe prescribing and administration.
Key drugs in midwifery
Know indications, doses, routes, and adverse effects of: oxytocin (induction and PPH; risk of hyperstimulation and water intoxication), magnesium sulfate (eclampsia prophylaxis and treatment; monitor reflexes, respiration, urine output; antidote calcium gluconate), ergometrine (contraindicated in hypertension), misoprostol, tocolytic agents, antibiotics for group B streptococcus prophylaxis and sepsis, antiretrovirals for prevention of mother-to-child transmission, and vitamin K for the newborn.
Safety practices
Use the five rights, check allergies, double-check high-alert drugs, calculate doses carefully, and know the antidotes. Understand drug compatibility with breastfeeding.
Traps
Oxytocin must be titrated, never bolused. Magnesium toxicity presents with loss of deep tendon reflexes before respiratory depression. Ergometrine raises blood pressure.
Rule of thumb
Before giving any drug, verify indication, dose, route, allergy, and monitoring parameters; if any is unclear, stop and check.