This document discusses various drugs acting on the uterus. It describes oxytocin, ergot alkaloids like ergometrine, and prostaglandins as the main classes of uterine stimulants. Oxytocin is used via intravenous infusion to induce or augment labor contractions. Ergometrine causes sustained whole uterine contraction and is used to control postpartum hemorrhaging. Prostaglandins like PGE2 and PGF2α induce rhythmic contractions and are administered intravaginally to induce abortion or labor.

1. Jincy Anna Iype
DRUGS ACTING ON UTERUS

2. Introduction
 Pregnancy
 Post Partum Haemorrhage (PPH)

3. • Oxytocin
• Ergot alkaloids
• Prostaglandins
• Misc. drugs
Stimulants
• ß2 selective agonist
• Calcium channel blockers
• MgSO4
• Oxytocin antagonist
• Misc. drugs
Relaxants
Classification

4. UTERINE
STIMULANTS
OXYTOCIN, DESAMINO OXYTOCIN
ERGOMETRIN
E,
METHYLERGO
METRINE
ETHACRIDINE, QUININE
PROSTAGLANDIN
ES
(PGE2, 15-methyl
PGF2α,
Misoprostol

5. OXYTOCIN

6. MECHANISM OF ACTION

7. Physiological role
• BREAST – milk ejection
 CVS- Transient vasodilation & tachycardia
-Constriction of umbilical arteries and veins
 CNS -Causes maternal behaviour
s
• KIDNEY – ADH like actions.

8. PHARMACOKINETICS
 Not absorbed orally
 Administered by i.v. , i.m. ,rarely nasal route.
 Plasma t1/2- approx. 15 mins
 It is primarily inactivated in the KIDNEY and the
LIVER.
 DOSAGE- OXYTOCIN, SYNTOCINON 2 IU/2ml
and 5 IU/ml inj. PITOCIN 5 IU/0.5ml inj.

9. USES
 Induction & Augmentation of labor:
 Oxytocin DOC
 i.v. infusion pump
 Dilution-5 IU in 500ml NS/Glucose
 0.2-2ml/mt. depending on response
contraindications:
﹡malposition
﹡cephalopelvic disproportion
﹡birth canal abnormality

10.  Postpartum hemorrhage :Third stage of labour,
5 IU i.m or i.v
infusion.
 Breast engorgement: Nasal spray before
suckling
 Oxytocin challenge test: To assess placental
insufficiency

11. ADVERSE EFFECTS

12. Desamino-oxytocin
 Buccal formulation, uses same as oxytocin, less consistent
action.
 INDICATIONS:
-Induction of labour : 50 IU every 10min, max 10 tablets
-Uterine inertia : 25 IU every 30 mins
- Promotion of uterine involution: 25-50 IU
- Breast engorgement : 25-50 IU before breast feeding
CARBETOCIN
•long acting structural analogue of human oxytocin
•given as a single IV bolus following the delivery of baby at Elective
or Emergency caesarean section.
•Carbetocin is as effective as an oxytocin infusion with respect to
blood loss following delivery
DOSE: Dilute 100mcg Carbetocin with 10mls Saline. Administer over one
minute following delivery of the baby

13. Ergometrine and Methyl ergometrine
 Amine ergot alkaloid and methyl derivative.
duration of uterine contractions
 Methyl ergometrine more potent action on
uterus and less on CVS, CNS, GIT etc.
 ACTION
 Increase force, frequency,
 Moderate increase of dose→Basal tone increased
 Lower segment also contracts.

14. USES
 Post Partum Haemorrahge(PPH )→
 After anterior shoulder presentation
Prevention → 0.2-0.3 mg i.m
Treatment → 0.5 mg i.v.
 Prevent uterine atony
 To promote involution in multipara →
0.125mg TDS -7days.
 Diagnosis of
variant angina during Coronary
angiography

15. ADRs
 Nausea, vomiting, rise in BP.
 Decreases milk secretion
 Avoided in Vascular disease, Hypertension,
toxemia
 Sepsis→gangrene
 Liver and kidney disease.
 Safe in obstetrical.doses
Contraindications:
in pregnancy & early stages of labour

16. PROSTAGLANDINS
 PGE2(Dinoprostone) → Vaginal application →
Induce II trimester abortion, missed abortion,
ripening of cervix in near term
Preperations-
 Misoprostol → with mifepristone for early abortion
 15-Methyl-PGF2α(Carboprost) → IInd trimester
abortions
 Facilitate labour- Unlabelled use in cardiac, renal
disease, eclampsia.

17. ETHACRIDINE
 Available as 50 mg/ml solution
 For extra-amniotic infusion
 EMCREDIL , VECREDIL

18. 1. Oxytocin
low dosage: rhythmic contraction of uterus;
fundus contracts while cervix relaxes;
used via ivd for induction or augmentation.
high dosage: sustained contraction in whole uterus;
used via im or iv for hemostasia or restoration of
postpartum uterus.
2. Ergot alkaloids
stimulation of sustained contraction in whole uterus,
ergometrine used via po, im or iv for hemostasia or restoration of
postpartum uterus;
stimulation of blood vessel constriction,
ergotamine used via po or im for migraine.
3. Prostaglandins
PGE2 & PGF2α stimulation of rhythmic uterine contraction,
used via ivd for induction (abortion)