Actions: 1. Oxytocin stimulates the uterus and cause physiologic type of contraction
- It also causes ejection of milk through contraction of the myo-epithelial cells
around the alveoli of the mammary gland.
Pharmacokinetics: It is inactivated orally and absorbed rapidly after intramuscular
administration. It can also be absorbed from nasal and buccal membrane.
Use: Induction of labor in women with uterine inertia, Relief of breast engorgement during
lactation (few minutes before breast feeding) as nasal spray, Postpartum hemorrhage.
Side effect: Oxytocin may cause over stimulation and leads to rupture of the uterus in the
presence of cephalo-pelvic disproportion. Therefore it’s contraindicated in woman with
uterine scar. When given intravenously may cause water retention leading to water
intoxication.
Prostaglandins
They induce labor at anytime during pregnancy but most effective at the third trimester. In
female reproductive system prostaglandin E & F are found in ovaries, endometrium and
menstrual fluid which is responsible for initiating and maintaining normal birth process. PGF,
PGF2ά, PGE stimulate both the tone and amplitude of the uterine contraction.
Adverse reaction: nausa, vomiting, headache, diarrhea, fever, etc.
PGs should be used cautiously in the presence of hypertension, angina, and diabetes. They are
contraindicated in the presence of cardiac, renal, pulmonary or hepatic disease
Ergometrine
It is one of the ergot alkaloids with the ability to cause contraction of the uterine smooth muscle.
It causes sustained uterine contraction. It is completely absorbed after subcutaneous and
intravenous administration. It is metabolized in the liver and eliminated in the urine .Liver
damage enhances the toxicity of ergot alkaloid.
Use: after delivery of placenta if bleeding is severe (Prevent postpartum bleeding)
Adverse effect: Nausa, vomiting but serious toxic effects are rare.

Leave a Reply