Obstetrics Drug Introduction Obstetrics medications can be broken down into the following categories diabetic agents hormone agonists hormone antagonists Endocrine Drug Table Obstetric Medications Inducers Name Mechanism of Action Key Indication Key Toxicity Oxytocin Acts via IP3 pathway Also has weak ADH properties Labor induction Uterine bleeding Breastfeeding Hyponatremia Increased heart rate Decreased blood pressure Misoprostol (PGE1) Cervical ripening Increases GI mucous production Labor induction Abortion Ulcers GI disturbance Dinoprostone (PGE2) Increases uteirne tone Labor induction Cervical ripening GI disturbance Fever Headache Tocolytics Name Mechanism of Action Key Indication Key Toxicity Terbutaline β2 agonist Tocolysis: indication 24-32 weeks indomethacin (first-line) nifedipine (second-line) 32-34 weeks nifedipine (first-line) terbutaline (second-line) Close PDA (indomethacin) Sympathetic symptoms (anxiety, tachycardia etc.) Hyperglycemia Indomethacin COX 1/2 inhibitor (NSAID) Tocolysis: indication 24-32 weeks indomethacin (first-line) nifedipine (second-line) 32-34 weeks nifedipine (first-line) terbutaline (second-line) Close PDA (indomethacin) Drowsiness Dizziness Ulcers Nifedipine Calcium channel blocker Tocolysis: indication 24-32 weeks indomethacin (first-line) nifedipine (second-line) 32-34 weeks nifedipine (first-line) terbutaline (second-line) Close PDA (indomethacin) Nausea Flushing Headaches Magnesium sulfate NMDA modulation thought to compete with calcium Pre-eclampsia Eclampsia (seizures) Torsades Bronchodilation Depressed deep tendon reflexes Drowsiness Cardiac arrest Respiratory depression Gynecologic Medications Estrogens Name Mechanism of Action Key Indication Key Toxicity Estradiol Estrogen receptor agonist Hormone contraception Hormone replacement therapy Breast cancer Endometrial cancer Ovarian cancer Menstrual Cycle Regulators Name Mechanism of Action Key Indication Key Toxicity Clomiphene citrate Estrogen receptor antagonist (particularly in the hypothalamus → increase GnRH) Fertility Ovulation induction Ovarian enlargement Visual symptoms Headaches