Uterine drugs Flashcards
DOC for inducing labor at term
oxytocin (Pitocin, Syntocin)
- IV infusion
what happens to uterine receptors prior to labor and deliverty
- number and sensitivity of oxytocin receptors in the uterus increase
uterus is generally resistant to stimulation during 2nd trimester but what can cause strong labor like contractions at this stage
prostaglandins
- useful in inducing abortions at this time
1st line treatment for postpartum hemorrhage
massage
indications for use for oxytocin
- induce labor at term if indicated: IV route
- prevention of hemorrhage: IM route
- stimulation of milk let-down reflex: nasal application
adverse effects of oxytocin
- water intoxication: due to ADH like effect
- uterine rupture with large doses
- anaphylaxis
- sinus bradycardia of fetus
CI to oxytocin
when you can’t deliver vaginally
List the Ergot Alkaloids
- Ergonovine maleate
- Methylergonovine Maleate
MOA of Ergot Alkaloids
contraction of uterine smooth muscle through activation of serotonin and alpha adrenergic receptors
when are Ergot Alkaloids used
-
after completion of labor and the delivery of the placenta to produce firm uterine contractions and to decrease uterine bleeding
- 2nd line after massage and oxytocin have failed
Contraindications to use Ergot Alkaloids
- should never be used to induce labor
- obliterative vascular or coronary artery disease
List the Prostaglandin drugs
- Dinoprostone (Prostin E2)
- Carboprost tromethamine (derivative of PGF2a)
when is Dinoprostone (Prostin E2) used
- expulsion of uterine contents
- intrauterine fetal death
- missed abortions
- elective abortions
- cervical ripening prior to delivery at term
adverse effects of Dinoprostone (Prostin E2)
- GI disturbances, vomiting, diarrhea - black box
- top 5 diarrhea producing drugs
list the top 5 diarrhea drugs
- “Many quality Drugs Expel Crap”
- Metformin
- Quinidine
- Dinoprostone
- Erythromycin
- Colchicine
when is use of Dinoprostone contraindicated
- for abortions, shoud not be used in patients with
- acute cardiac, pulmonary, renal, or hepatic diseases
- asthma, HTN, anemia, jaundice, or epilepsy
when is Carboprost tromethamine used
- induced abortion in 13th and 20th week
- postpartum bleeding due to uterine atony
- 3rd line after massage, oxytocin, and ergots
adverse effects of Carboprost tromethamine
- vomiting and diarrhea
when is use of Carboprost tromethamine contraindicated
- should not be used in patients with
- acute cardiac, pulmonary, renal, or hepatic diseases
- asthma, HTN, anemia, jaundice, or epilepsy
define premature labor
labor before the fetus has matured sufficiently for survival (37th week)
primary risk factor for premature labor
previous preterm labor or preterm birth
what can be given if delivery will happen before 37th week
corticosteroids: develop fetal lungs
* no option for stopping preterm labor is FDA approved
MOA of Magnesium sulfate
relaxes the uterus probably by a direct effect
1st line drug (prefernce) for stopping preterm labor
Magnesium sulfate
use of Magnesium sulfate
- 1st line to relax the uterus and prevent preterm labor
- can prevent convulsions in pre-eclampsia and treat eclampsia
route of administration of Magnesium sulfate
IV
adverse effects of Magnesium sulfate
flu-like symptoms
MOA of Nifedipine
- L type calcium channel blockers
- inhibits Ca2+ influx (smooth muscle contractions)
use of Nifedipine in labor
becoming 1st line agent for preventing preterm labor
MOA of Indomethacin
- strong inhibitor of COX enzymes -> reduce prostaglandin synthesis
Use of Indomethacin in labor
- 2nd line drug for preventing preterm labor
adverse effects of Indomethacin
- partial closure of fetal ductus arteriosus
Indications for use of Progesterone in preventing perterm labor
- maintains length of pregnancy when given prophylactically from the 16th -37th weeks of pregnancy or until delivery
- not effective for acute treatment
- recommended for high risk women with a h/o preterm birth
Indications for use of Nitroglycerin during labor
- Emergency use only
- in case of uterine rupture
