Drugs acting uterus are discussed in that ppt . Uterus stimulants and uterus relaxants are discussed here Thanking you Have a nice day and nights

1. DEPARTMENT OF PHARMACEUTICAL SCIENCES,
MDU ROHTAK
Submitted to :-
Mrs. Anuradha Pannu
Pharmacology Theory Assignment
DRUGS ACTING ON THE UTERUS
STIMULANTS AND RELAXANTS

2. • Part of female reproductive system , known as womb.
• Consist of three layer
1. Endometrium – inner layer of uterus
2. Myometrium- smooth muscle, middle layer of uterus
3. Perimetrium- protective, upper layer of uterus
• Drugs acts on inner and middle layer mostly.
• Drugs classified as
1. Uterus stimulant 2. Uterus relaxant
Uterus – womb

3. Drugs acting on uterus
Uterine stimulants :
• These drugs increase uterine motility.
• They are classified as follows
1) Posterior pituitary hormone : Oxytocin,
Desamino oxytocin .
2) Ergot alkaloids: Ergometrine
(Ergonovine), Methylergometrine
3) Prostaglandins : PGE2, PGF2α, 15methyl
PGF2α, Misoprostol .
4) Miscellaneous : Ethacridine, Quinine.
Uterine relaxants
• Also known as tocolytics
• Decrease uterine motility.
• These are classified into 5 classes
1) Adrenergic agonists
2) Calcium channel blockers
3) Oxytocin antagonist
4) Magnesium sulfate
5) Miscellaneous drugs.

4. Oxytocin :-
• nonapeptide secreted by the posterior pituitary along with vasopressin (ADH).
• Both oxytocin and ADH are synthesized within the nerve cell bodies in supraoptic and
paraventricular nuclei of hypothalamus; are transported down the axon and stored in the
nerve endings within the neurohypophysis.
Pharmacological actions
1.Uterus
Increase contraction force and frequency
Estrogen sensitize the uterus and increase oxytocin receptors
Sensitivity increase in 3rd trimester
Oestrogens and estrogen increase uterus sensitivity towards oxytocin and
progestin decreases

5. 2.Breast
 Contracts the myoepithelium of mammary alveoli
and forces milk to the bigger milk sinusoids.
 Milk ejection reflex
3.Cvs
• No effect except at high dose
4.Kidney
• No effect except at high dose
 Physiocological roles
 Milk Ejection Reflex.
 Labour.
 Neurotransmission.
 At low dose show normal relaxation between contractions

6. Pharmacokinetics
 Ineffective orally
 Administered by i.m. or i.v. routes
 Rapidly degraded in liver and kidney
 Induction of labor
 Uterine inertia
 Post partum hemorrhage and caesarean
section treatment
 Breast engorgement
Adverse effects
• Uterine hyperstimulation
• Water intoxication
• Headache
• Convulsions

7. Ergometrine and methylergometrine
• Natural ergot alkaloid while methylergometrine is semi synthetic.
Pharmacological actions
1.Uterus
 Increase forces and frequency, duration of contractions
 At low dose, normal relaxation
2.CVS
 Weaker vasoconstriction
 Raise in BP
3.CNS and GIT
 No effect except at high dose

8. Adverse effect:-
 Less toxic
 Nausea
 Rise in BP
 Vomiting
 Decrease milk secretion
 Avoided for GIT, liver and kidney patients
Pharmacokinetics
Administered orally
Takes less time on i.v. route
Half life time period is 1-2 hours

9. Prostaglandins:-
PGE2, PGF2α and 15methyl PGF2α
 potent uterine stimulants
Used in the later part of pregnancy
 cause ripening of cervix

10. Adrenergic Agonists:-
Ritodrine
 the β2 selective agonist
 prominent uterine relaxant action
Dose increase according to response
Adverse effects
a)Hyperglycemia
b)Hypokalamia
c)Headache
d)Arrhythmia
salbutamol and terbutaline are used as
alternative of ritodrine

11. Calcium channel blocker:-
• Because influx of Ca2+ ions plays an important role in uterine contractions, Ca2+ channel
blockers
• reduce the tone of myometrium and oppose contractions.
• can postpone labor if used early enough.
• Less side effects as compared to the β2 selective agonist
• Need intense care after calcium channel blocker therapy

12. Figure: different
mechanisms of
different uterus
relaxants
• Calcium channel blockers
• Magnesium sulfate
• β2 selective agonist
• NO donors
• Oxytocin antagonists

13. Magnesium sulphate
• First line drug got prevention and treatment of seizures in preeclampsia and eclalmpsia
• Acts as a tocolytic by competing with calcium ions entry into myometrium.
• Use to delay premature.
Miscellaneous drugs.
• Depress uterine contractions
• Not clinically used as tocolytics
• Halothane – effective uterine relaxant
• Used as anesthetics

14. Reference:-
• Tripathi KD, Essentials of Medical Pharmacology,7th edition, Jaypee Brothers Medical Publlishers, Private
limited ,Page no.329-34
• Shanbhag TV, Shenoy S, Pharmacology for Medical Graduates, 3rd edition, Elsevier Relax India private
limited, page no. 397-402
• Mudagal M.P., Sharma U. Raj, A textbook of Pharmacology-ii, 1st edition , sept,2019, Nirali Prakashan,
advancement of knowledge, page no. 23.1-23.6
• Brunton l, parker k, blumenthal d, buston l, goodman and gilman’s manual of pharmacology and
therapeutics, mc graw hill campanies , page no. 977-979
• Bruntoon l, goodman and gliman’s the pharmacological basis of therapeutics,13th edition, mc graw hill
education company, page no.783-785.
• https://www.slideshare.com.
• https://www. career medical.com
• https://www.pharmacy180.com
• https://www. researchgate.Com

15. THANKING YOU
Any Doubt ?