Oxytocin Injection: Uses, Dosage, Side Effects, Precautions and Alternates

Quick overview

Oxytocin Injection contains a man-made version of oxytocin, a natural hormone that triggers uterine contractions. It is used in hospital settings to start or strengthen labour, to help manage certain types of miscarriage, to support contractions during and after delivery (including caesarean section), and to prevent or control bleeding after childbirth. It is given only under close medical supervision, usually as a slow intravenous infusion or, for bleeding control, as a single injection into a muscle.

What is Oxytocin Injection

Oxytocin Injection contains a man-made version of oxytocin, a natural hormone that is normally stored in the posterior pituitary gland and released during labour and breastfeeding. It acts on the uterus to cause contractions.

Oxytocin Injection uses

• Starting or helping contractions during childbirth (induction or stimulation of labour) for medical reasons
• Helping manage incomplete, inevitable, or missed miscarriage/abortion
• Producing uterine contractions during and after delivery, including during a caesarean section
• Preventing and controlling bleeding (haemorrhage) after childbirth

Benefits of Oxytocin Injection

• Helps start or strengthen labour contractions when there is a medical reason to do so
• Helps control or stop heavy bleeding after childbirth
• Helps the uterus contract during caesarean section after the baby is delivered

How Oxytocin Injection works

Oxytocin attaches to receptors in the muscle of the uterus, which triggers the release of calcium inside the muscle cells. This calcium increase causes the uterus muscle to contract, similar to contractions seen in natural labour.

Oxytocin Injection dosage

This medicine is given only in a hospital under close medical supervision by trained staff. For starting or strengthening labour, it is given only as a slow intravenous drip (infusion), never as a rapid injection into a vein, and never by muscle or under-the-skin injection for this purpose. For controlling bleeding after birth, it may also be given as a single injection into a muscle.

The infusion bottle or bag should be turned upside down several times before use to mix it evenly. You and your baby will be closely monitored throughout treatment, including contraction pattern and your baby's heart rate. You may be told to limit how much fluid you drink while receiving this medicine.

This medicine should not be given at the same time as certain other medicines called prostaglandins used to start labour; there should be a gap of several hours between the two. It is not intended for use in children, adolescents, or elderly patients, as there is no information on use in these groups.

Use exactly as prescribed by your doctor or pharmacist.

Available forms and strengths

• Injection
• Nasal Spray

Side effects of Oxytocin Injection

Common

• Nausea
• Vomiting
• Headache
• Fast or slow heartbeat
• Intense and frequent contractions

Serious

• Severe allergic (anaphylactic) reaction with difficulty breathing, dizziness, feeling faint, cold clammy skin, or fast/weak pulse
• Swelling of face, lips, tongue, throat, or limbs (angioedema)
• Irregular heartbeat (arrhythmia)
• Rupture of the uterus
• Excessive bleeding after childbirth (postpartum haemorrhage)
• Water intoxication with headache, loss of appetite, nausea, vomiting, stomach pain, drowsiness, unconsciousness, or seizures
• Low blood salt levels (hyponatraemia)
• Sudden fluid buildup in the lungs (pulmonary oedema)
• Abnormal blood clotting, bleeding, and anaemia (disseminated intravascular coagulation)
• Chest pain (angina) or myocardial ischaemia
• Low blood pressure with flushing and rapid heartbeat, especially with rapid injection
• Harm to the baby, including low blood salt levels, shortage of oxygen, suffocation, or death from excessive contractions

Warnings and precautions

This medicine must only be given in a hospital by trained healthcare staff who can watch for complications, with a doctor available to manage any problems. Giving too much oxytocin, or administering it improperly, can overstimulate the uterus and be dangerous for both mother and baby, even when properly supervised in sensitive patients.

This medicine should not be given by rapid injection into a vein because it can cause a sudden drop in blood pressure, a brief feeling of heat over the body, and a fast heartbeat. Receiving large amounts of fluid along with this medicine over a long time can cause the body to retain too much water, leading to symptoms such as feeling very full, difficulty breathing, and low salt levels in the blood.

People with a latex allergy should tell their doctor, since the active ingredient may cause a severe allergic reaction in such patients. This medicine must not be used when vaginal delivery is not advisable, for example if the baby's head cannot fit through the pelvis, the baby is in the wrong position, or the placenta blocks the birth canal.

Oxytocin is not expected to be a risk to the baby when used correctly and as indicated. It should only be used in pregnancy for the medical induction of labour or in relation to miscarriage/abortion, not for convenience.

Oxytocin may pass into breast milk in small amounts, but it is not expected to harm the baby because it is broken down quickly in the baby's digestive system.

Tell your doctor if you have kidney problems, because oxytocin can cause the body to retain water, and reduced kidney function may cause the drug to build up in the body.

There is no specific information on use in patients with liver disease.

It is not known how oxytocin interacts with alcohol, so you should check with your doctor before drinking alcohol.

Oxytocin can start labour, so women who are having contractions should not drive or use machinery.

Storage

• Store at 20° to 25°C (68° to 77°F), USP Controlled Room Temperature (per Fresenius Kabi source)
• Store below 25°C and protect from light (per NZ data sheet)
• Store between 2°C and 8°C in a refrigerator; do not store at room temperature (per hameln and Hikma sources)
• Do not freeze
• Use only if the solution is clear and the seal is intact; discard any unused portion
• Keep out of the sight and reach of children
• Do not throw away medicines via wastewater or household waste; ask your pharmacist how to dispose of unused medicine

When to see a doctor

• Get medical help right away if you have signs of a severe allergic reaction, such as difficulty breathing, dizziness, feeling faint, nausea, cold and clammy skin, or a fast or weak pulse.
• Tell your doctor straight away if you notice swelling of the face, lips, tongue, throat, or limbs, which may be signs of a serious allergic reaction.
• Seek immediate medical attention if you have symptoms of water retention such as headache, loss of appetite, nausea, vomiting, stomach pain, extreme sleepiness, or seizures.
• If you think you or someone else has received too much of this medicine, tell hospital staff or a doctor immediately.

Alternatives

• Misoprostol
• Carboprost
• Mechanical Cervical Ripening Methods