Uterotonics are drugs that induce or augment uterine contractions. The main uterotonics used are oxytocin, ergot derivatives, and prostaglandins. Oxytocin is a nonapeptide hormone produced naturally during labor and delivery. It is administered via intravenous or intramuscular routes to induce or augment labor. Ergot alkaloids like ergometrine are derived from fungi and act by vasoconstriction. Prostaglandins like misoprostol are produced in the body and work by changing cell membrane permeability. Each drug has specific indications, contraindications, dosing, and side effects that must be considered when selecting the appropriate uterotonic for labor induction or management.

1. Uterotonics
Dr Ravikanth G O

2. • Ecbolics
• Induce uterine contractions
• What is the opp of uterotonics ?
• Oxytocin
• Ergot derivatives
• Prostaglandins

3. Oxytocin
• Nonapeptide
• Sir de vigneaud – Nobel prize
• Onset 3-4 min
• Duration 20 min

4. Mode of action

5. Preparations

7. Effectiveness of oxytocin

8. Indications
• Therapeutic
1. Pregnancy
2. Labor
3. Puerperium
• Diagnostic
1. Contraction stress test
2. Contraction sensitivity test

9. During Pregnancy
• Early -- abortion
• Late -- induction of labor

10. During labor
Ripen the cervix
Augmentation of labor
Active management of third
stage of labor

11. During
puerperium
Postpartum
haemorrhage
Problem of breast
I,e. Breast congetion

12. Complications
of oxytocin –
Maternal.
Uterine hyperstimulation
Uterine rupture
Water intoxication
Hypotension
Antidiuresis

13. Complications
– Fetal.
• Fetal distress

14. What are the Routes of administration?
• Intravenous bolus
• Intravenous infusion (CII-controlled intravenous infusion)
• Intramuscular
• Buccal tablets
• Nasal spray

15. Controlled intravenous infusion
• Infusion pump
• For induction or
augmentation of labor
• Physiological titration

16. Calculation of
dose
Ampule 1 ml = 5 IU
Add 4 ml saline to it =1iu/ml
1IU = 1000 miu
Add 1IU in 500 ml of NS/RL.
500ml = 1000 iu
1ml = 2iu
1ml = 16 drop/min
1IU in 500 ml of RL run at the rate 8 drop/ min =1miu/min

17. Exercise
• Start 2miu/min
• 2iu is added to 500 ml of RL and running at the rate of 32 drop/min
calculate the dose I,e. miu./min
• What do you mean by strong uterine contrations?

18. Oxytocin
regime Low dose
High dose

19. How do you Monitor oxytocin CII ?
• Rate
• Uterine contraction
• Peak intrauterine pressure
• FHR
• PROGRES OF LABOR

20. What are the indications of stopping
infusion?
• Abnormal uterine contration
• Fetal distress
• Maternal exhaustion

21. Diagnostic use
• Contraction stress test ( Oxytocin challenge test)
• Cardiotocograph is done

22. Interpretation of CST
• Positive
• Negative
• SUSPICIOUS
• Unsatisfactory
• Hyperstimulation

23. Ergot derrivatives
• Ergometrine
• Methyl ergometrine
• Alkaloid isolated by Dudley & Moir from
fungus CLAVICEPS PURPURA
• Methergin - semisynthetic derived fro LSD.
• Mode of action
• Where is it can be sued ?

24. Mode of
administration
Ergometrine
• Iv 50 sec
• Im. 5 min
• Oral 10 min
Methergine
• IV 1 ½
• IM 7 min
• Oral 10 min

25. Complications
GI symptoms
Vasocontriction - MI, HT,
stroke, bronchospasm.
Gangrene of toe
Lactation

26. Contraindication
- Prophylactic
Multiple pregnancy
Cardiac disease
Pre-eclampsia & eclampsia
Rh-ve mother

27. Contraindication - Therapeutic
Pregnancy
Heart
disease

28. Prostaglandins
Prostonoic acid derivative
Isolated from prostate by VonEuler
PG E1,
PG E2
PG F2alpha
Produced from decidua,membrane,myometrium
Effacement of cervix
Physiologic contraction of uterus

29. Mechanism of
action
Change in cell
membrane permeability
PGE2 on Body of uterus
& cervix.
PGF 2 alpha -
Myometrium

30. Indications
MTP -- Medical Surgical &
combined.
Molar pregnancy
Induction of labor
PPH

31. Contraindications
Hypersensitivity
Scared uterus
Active Cardiac,hepatic,renal ,or
pulmonary disease
Asthma

32. Match the fallowing drugs to its dose
Name of drug Dose Response
1.oxytocin A.100 microgram
2. Methergine B.0.5mg+5IU
3. Misoprostol(PGE1) C.5IU
4. Dinoprost (PGE2) D.250 microgram
5.Prostodine(PG F2 Alpha) E.0.2mg
6.Synometrine F.25microgram
Answer : 1-C,2-E,3-F,4-A,5-D,6-B.

33. Evaluation 1
• What is oxytocin ?
• Why we can not use oxytocin by oral route ?
• What are the indications of Oxytocin ?
• What are the routes of administration of Oxytocin ?
• What are the contraindications of Oxytocin ?
• What are the side effects of Oxytocin ?
• What are the regime of oxytocin?
• How do you prepare 5miu/min solution?

34. Evaluation 2
• What are the diagnostic use of oxytocin ?
• What is ergot ?
• What are the ergot derivatives used in clinical practice?
• What are the indication of ergot ?
• Why ergot can not be used in induction of labor?
• What are the preparation of ergot available ?
• What are the side effects of ergot ?

35. Evaluatioin 3
• What are prostaglandins ?
• What are the type PGs used in clinical practice ?
• A primigravida with full term pregnancy with h/o asthm.Indicate the
method of induction of labor &
• what we should avoid?
• What are the side effects of prostaglandins?