Oxytocin Pharmacology

Oxytocin

About Oxytocin
A short polypeptide hormone from posterior pituitary gland, Oxytocic, Antihemorrhagic.
Mechanism of Action of Oxytocin
Oxytocin binds to G-protein coupled receptors. In human myometrium these receptors couple to Gq and G11 receptors. This will activate Phospholipase -C hydrolysis and generate Inositol triphosphate (IP3) and Diacyl glycerol. These will mobilizes calcium ion from calcium deposits and also enhances voltage sensitive Ca2+ channels. This Ca2+ produces contraction. Oxytocin also increases local prostaglandin production and stimulates uterine contractions.
Pharmacokinets of Oxytocin
Absorption: It is well absorbed after parenteral administration.
Distribution: It is distributed mainly to extracellular fluid and small amount enter in the fetal circulation.
Metabolism: Oxytocin is metabolised in the kidney and liver.
Excretion: Excreted mainly in the urine.
Onset of Action for Oxytocin
Immediate (IV), 3 - 5minutes (IM)
Duration of Action for Oxytocin
1 hour (IV), 2 - 3 hours (IM)
Half Life of Oxytocin
1 - 6 minutes
Side Effects of Oxytocin
1. Hypersensitivity reaction
2. Premature ventricular contractions
3. Postpartum hemorrhage
4. Subarachnoid hemorrhage
5. Pelvic hematoma
6. Nausea
7. Vomiting
8. Cardiac arrhythmia
9. Hypertensive episodes
10. Fatal afibrinogenemia
11. Rupture of the uterus
Contra-indications of Oxytocin
1. Hypersensitivity to Oxytocin
2. In unfavorable fetal positions (transverse lies, which are undeliverable without conversion prior to delivery)
3. In obstetrical emergencies
4. In fetal distress where delivery is not imminent
5. Where adequate uterine activity fails to achieve satisfactory progress
6. Where the uterus is already hyperactive or hypertonic
7. Invasive cervical carcinoma
8.Active herpes genitalis
9.Total placenta previa, vasa previa
10.Prolapse of the cord
11.Cephalopelvic disproportion
Special Precautions while taking Oxytocin
1. 1st and 2nd stages of labor
2. Uterine surgery
3. Cervical surgery
4. Uterine sepsis
5. Grand multiparity
6. Overdistended uterus
7. Traumatic delivery
8. Invasive cervical cancer
Pregnancy Related Information
Contraindicated
Old Age Related Information
Contraindicated
Breast Feeding Related Information
Contraindicated
Children Related Information
Contraindicated
NEONATES : Contraindicated
Indications for Oxytocin
1. Induction of labour
2. Augmentation of labour
3. Reduction of postpartum bleeding
4. Induce abortion
5. Oxytocin challenge test
Interactions for Oxytocin
Sympathomimetics: Pressor effect of sympathomimetics may be increased leading to postpartum hypertension.
Prostaglandins: Risk of uterine repture & cervical lacerations.
Ergotamine: Synergistic effect in control of post partum haemorrhage.
Typical Dosage for Oxytocin
Intravenous or intramuscular
Adult:
1. Induction of labour: Initial dose: 0.5- 1 milliunits /minute as IV infusion and if needed rate can be gradually increased by 1 - 2 milliunits/minute until sufficient response is obtained.
2. Augmentation of labour: Initial dose: 2milliunits/minute as intravenous infusion and then gradually increase the dose maximum up to 20milliunits/minute
3. Reduction of postpartum bleeding after expulsion of placenta: 20 - 40 milliunits/minute as intravenous infusion after delivery of placenta.
4. Induce abortion: 10 - 100 milliunits/minutes
5. Oxytocin challenge test to assess fetal distress in high risk pregnancies greater than 31 weeks` gestation: Initial dose: 0.5milliunits/minute followed by gradual increase in infusion rate every 15 minutes up to 20milliunits/minute. When 3 moderate uterine contractions occur in a 10 minute interval then stop the use of medicament.
Schedule of Oxytocin
H
Storage Requirements for Oxytocin
Store at 2 - 8 degree C.
Effects of Missed Dosage of Oxytocin
Do not apply.
Effects of Overdose of Oxytocin
Give supportive measures and symptomatic treatment.

Home Delivery for Oxytocin in Your City

Medicine India is just a publishing medium for medicine related information and does not provide services or sales of medicines including oxytocin.

However, we do publish a comprehensive directory of Pharmacies, Chemists and Druggists in cities all over India. You can use this directory to find the medicine stores in your city (or area) that provide home delivery services for oxytocin and other medicines and health products. Home delivery services for oxytocin may be free or they may cost you depending on the pharmacy and the minimum order requirements. It would be best to get this clarified while placing the order.

Please be aware that you should take oxytocin only if a doctor has recommended or prescribed it. Some or all pharmacies who provide a home delivery service for medicines might insist on a prescription for oxytocin before they complete the sale. You can get this information while placing the order for oxytocin with the pharmacy.

Oxytocin is a generic medicine name and there are several brands available for it. Some of the brands for oxytocin might be better known than oxytocin itself. If the pharmacy that's willing to deliver medicines to your home doesn't have oxytocin in stock, you can ask for one of the branded alternatives for oxytocin.