Uterus stimulant drugs as per PCI syllabus

1. ECBOLICS

2. ECBOLICS:
also known as
A uterotonic, Uterine stimulant
it is an agent used to induce contraction or greater
tonicity of the uterus.
 Uterotonics are used both to induce labor, and
to reduce postpartum hemorrhage.

3. Drug acting on uterus can primarily affects the
endometrium or myometrium.
ESTROGEN, PROGESTINS & THEIR ANTAGONIST –
Mostly affecting the endometrium
UTERINE STIMULANTS:
”Drugs which increase
uterine motility”

4. CLASSIFICATION OF UTERINE STIMULANTS:
POSTERIOR PITUITARY HORMONE:
 OXYTOCIN
 DESAMINOOXYTOCIN
ERGOT ALKALOIDS:
 ERGOMETRINE
 METHYLERGOMETRINE
PROSTAGLANDINS:
 PGE2
 PGF2α
 MISOPROSTOL
MISCELLANEOUS:
ETHACRIDINE
QUININE

5. OXYTOCIN:
 It is a nanopeptide secreted by posterior pituitary
along with vasopressin (ADH)
 Both oxytocin and ADH are synthesized with in nerve
cell bodies in supraoptic and paraventricular nuclei of
hypothalamus.
 They are transported down the axon and stored in the
nerve ending within the neurohypophysis (posterior
pituitary)
 Stored in the separate neuron as complexes with their
specific binding proteins (neurophysins)
 On stimulation
Coitus, parturition (child birth), sucking -oxytocin
Hypertonic saline infusion, water deprivation,
hemorrhage – ADH

7. ACTIONS:
UTERUS:
Increase force and frequency of uterine contractions.
With lower dose full relaxation occurs between the
contraction
Basal tone increases only with higher doses
Increase contractility due to hightened electrical
activity of the myometrial cell membrane.
Sensitivity increases during third trimester
The increased contractility is restricted to the fundus
and body

9. MECHANISM OF ACTION:
OXYTOCIN BINDS TO SPECIFIC G- PROTEIN COUPLED
OXYTOCIN RECEPTORS PRESENT IN THE UTERUS
↓
DEPOLARIZATION OF MUSCLE FIBRES AND Ca2+ IONS INFLUX
↓
CONTRACTION
Number of oxytocin receptor increase during later part of
pregnancy.
Oxytocin increase PG synthesis and released by
endometrium which contribute to the contraction

10. BREAST:
Produce Milk ejection reflex by the contraction of
myoepithelium of mammary alveoli & forces the
milk in to the bigger milk sinusoids
CVS:
• No effect in conventional dose
• Fall in B.P, vasodilation, reflex tachycardia occurs
with higher dose.

12. PHYSIOLOGICAL ROLE:
LABOUR:
Oxytocin released during labour
uterus highly sensitive to it at this time
Labour
MILK EJECTION REFLEX
NEURO TRANSMISSION
USE:
Induction of labour
Post partum hemarrhoage

13. THANK
U