How long does oxytocin take to work?

Many pregnant women in the later stages of pregnancy will pay special attention to some things in the delivery process. Oxytocin is a drug used to treat uterine bleeding caused by weak or poor uterine contractions during induction of labor, acceleration of labor, and postpartum labor. Oxytocin is usually used in the form of injection, because if oxytocin is taken orally it will be destroyed by digestive juices and become ineffective. There are also some things to pay attention to when using oxytocin.

How long does oxytocin take to work?

Oxytocin takes effect within 3 to 5 minutes after intramuscular injection, and the effect lasts for 30 to 60 minutes; intravenous infusion takes effect immediately, and the frequency and intensity of uterine contractions gradually increase within 15 to 60 minutes, and then stabilize. Its effect gradually subsides 20 minutes after the completion of the infusion. The half-life is generally 1 to 6 minutes. This product is metabolized by the liver and kidneys and excreted by the kidneys, with only a very small amount remaining in its original form.

Precautions for Oxytocin Injection:

(1) The drug should be used with caution in the following situations: patients with heart disease, borderline cephalopelvic disproportion, history of intrauterine infection, previous cervical surgery, cervical cancer, premature birth, unengaged fetal head, and pregnant women over 35 years of age. When using the drug, be alert to the possibility of fetal abnormalities and uterine rupture.

(2) The use of oxytocin during caudal block may cause severe hypertension or even cerebral vascular rupture.

(3) Inspection and monitoring are required before and during medication:

① The frequency, duration and intensity of uterine contractions;

②Pregnant woman’s pulse and blood pressure;

③Fetal heart rate;

④ Uterine muscle tension during rest;

⑤ Fetal maturity;

⑥ Pelvic size and fetal presenting part descent;

⑦ Balance of fluid intake and output (especially for long-term users).

Mild adverse reactions may occur with the use of oxytocin injection, including occasional nausea, vomiting, increased heart rate, or arrhythmia. Large doses may cause hypertension or water retention. However, using it according to the doctor's instructions can greatly reduce the occurrence of adverse reactions.

In addition, everyone should pay attention to the fact that long-term medication is ineffective for patients with a narrow pelvis, obstructed birth canal, obvious cephalopelvic disproportion and abnormal fetal position, a history of cesarean section, a history of myomectomy, umbilical cord presentation or prolapse, placenta previa, fetal distress, excessive uterine contractions, and weak uterine contractions.