Oxytocin is indicated for
The active ingredient of this preparation is synthetically produced oxytocin, which is identical to the naturally occurring hormone released from the posterior pituitary gland.
Oxytocin causes uterine contractions similar to those of normal spontaneous labor and temporarily reduces uterine blood flow. It increases the strength and duration of contractions, helping cervical dilation and effacement. It also stimulates the smooth muscles around the secretory epithelium of the lactating breast, promoting milk ejection through the mammary ducts, although it does not directly increase milk production. Oxytocin has only minimal cardiovascular and antidiuretic effects, making it relatively safe for patients in whom a rise in blood pressure should be avoided, such as those with hypertension, toxemia, pre-eclampsia, placental abruption, or uremia.
Uterine motility depends on the formation of the contractile protein actomyosin under the influence of the calcium-dependent phosphorylating enzyme myosin light-chain kinase. Oxytocin promotes uterine contractions by increasing intracellular calcium levels, which activates myosin light-chain kinase. It binds to specific receptors in the muscle lining of the uterus, and the number of these receptors increases significantly during pregnancy, reaching the highest level during early labor at term.
Induction of labor, stimulation of uterine contractions: Oxytocin should be given by intravenous infusion under adequate control, 1–5 IU added to 500 ml of infusion fluid. The administration is started at 1 mU (1 mU = 0.001 IU) per minute. According to the effect obtained the dosage can be doubled every 30–45 minutes until the uterus threshold has been attained. A further increase will then usually provide optimal activity. The threshold is generally below 10 mU per minute.
N.B.: Intramuscular administration of Oxytocin may lead to an irregular response and symptoms of overdosage. If intramuscular administration is nevertheless unavoidable, dosage should not exceed 0.5–1 IU per injection.
Post delivery period, for the prevention or treatment of secondary haemorrhage and adherent placenta: Intramuscular injection of 2–5 IU, or as intravenous infusion in an adequate dosage.
To stimulate lactation, only if advised by the registered Gynaecologist/Physician: Intramuscular injection of 2 IU.
Treatment of incomplete abortion to obtain more rapid expulsion in order to prevent secondary hemorrhage: Intramuscular injection of 2–5 IU every 30–60 minutes or as intravenous infusion in an adequate dosage.
Severe hypertension has been reported when oxytocin was administered 3–4 hours after prophylactic use of a vasoconstrictor in combination with caudal block anesthesia. Cyclopropane anesthesia may alter the cardiovascular effects of oxytocin, potentially leading to unexpected outcomes such as hypotension. Maternal sinus bradycardia and abnormal atrioventricular rhythms have also been observed when oxytocin was used together with cyclopropane anesthesia.
Oxytocin is contraindicated in the following conditions:
In rare cases, water intoxication symptoms may develop, and an increased incidence of neonatal jaundice has been reported.
Pregnancy Category C. It is not known whether oxytocin is excreted in human breast milk.
Excess oxytocin may cause strong uterine contractions leading to fetal bradycardia, arrhythmias, severe soft tissue injury, uterine rupture, and possibly maternal or fetal death. Treatment includes immediate discontinuation of the drug and initiation of tocolytic therapy.
Drugs acting on the uterus.
Store between 2°C and 8°C in a dark, frost-free place. Keep out of reach of children.
What is Oxytocin for?
What does Oxytocin do?
What are the side effects of Oxytocin?
What happens if you take too much Oxytocin?
Can Oxytocin be taken during pregnancy?
