Oxytocin is a hormone that contracts smooth muscle to help expel the fetus during delivery and eject breastmilk. It is released naturally during labor and delivery in response to cervical and nipple stimulation. It can also be administered synthetically through intravenous or intramuscular injection to induce or augment labor. Potential adverse reactions include seizures, hypotension, and uterine rupture. Proper assessment of the patient's risk factors and careful titration of dosage are important when using oxytocin for labor induction or augmentation.

1. Pharmacotherapy in Obstetric
& Gynaecology: OXYTOCIN
NAZNEEN VAHORA
CLINICAL INSTRUCTOR
MTIN,CHANGA

2. ACTIONACTION
 It is released in large amounts after distension of cervix
and vagina, nipple stimulation.
 It contracts smooth muscle helping the expulsion of the
foetus and ejection of breastmilk.
 It also crosses the placenta and acts on the foetus
neurons to prepare it for delivery- to sedate the brain.
 Rapid acting: 1 minute if given IV; 3-7 minutes if given
IM and lasts 30-60 minutes.

3. POTENTIAL ADVERSEPOTENTIAL ADVERSE
REACTIONSREACTIONS
 Seizures, subarachnoid haemorrhage
 Tachycardia, hypotension, arrythymias
 GU: uterine rupture, pelvic hamatoma, PPH, hypertonic
uterine contractions
 Foetal distress from Hypertonic U- increases c/s rate
 Rapid or prolonged infusion causes water retention
 Neonatal jaundice –crosses placenta.
 Do not give rapid IV bolus for PPH ; hypotension

4.  Large doses- sustained contraction(↓ placental
blood flow & fetal hypoxia/death)

5. SOURCESSOURCES
 Corpus Luteum
 PLACENTA ( may be foetus starts the
labour)
 Synthetic pitocin

7. USESUSES
 Augmentation labour
 Induction labour
 PPH
 Retained products conception
 PIH patients – post partum

8. • Clinical use:
- IOL (IVI 3U syntocinon+50 ml of saline)
- Augment slow labour (IVI same as above)
 3rd
stage of labour- 5 U IM for HTN ,
 cardiac disease- IVI 40 U in 500ml saline ( PPH)
 Surgical termination of preg./ERPC (Evacuation of
retained products of conception) - 5U slow IV

9. ASSESSMENT BEFOREASSESSMENT BEFORE
augmentation/ inductionaugmentation/ induction
 Previous c/s or other uterine surgery?
 Twins?
 CPD? History of CPD or borderline now.
 Foetal distress?
 Malpresentation including cord presentation
 Praevia
 Bishop score ( induction)

11. DOSAGESDOSAGES
 Post partum -10u IMI on delivery of baby.
Can be repeated.
 PPH & RPOC (retained products of
conception) – 20u in 1 liter MRL run @ 20ml
/hr
 Augmentation primipara- 5u in 1 liter RL
titrated via IVAC to get regular contractions
and reactive CTG (5ml/hr increasing 1 ml/hr)
 Augmentation multipara – 2 u in 1 liter RL
titrated via IV to give regular contractions &
reactive CTG

12.  Pitocin should be piggybacked so that it can
be stopped if necessary and IV line can then
run.
 Pitocin is used for PIH patients because
syntometrine contains ergometrine (+pitocin)
and it causes round muscle contraction –
veins/arteries- so raises blood pressure.
 Pitocin can also be injected into placental
umbilical vein to get separation. (10u in 10ml)

13. STORAGESTORAGE
 15-25o
C – i.e. a fridge item.

14. PIGGYBACK IVPIGGYBACK IV