Pitocin 5 IU/ml (IM/IV Injection)

Indications

• Induction of labor
• Stimulation of uterine contractions
• Prevention or treatment of secondary hemorrhage
• Adherent placenta
• Stimulate lactation
• Treatment of incomplete abortion
• Prevent secondary hemorrhage

Description

• Active substance: synthetically prepared Pitocin
• Identical to natural occurring hormone
• Causes contractions of the uterus
• Mimics contractions of normal labor
• Impedes uterine blood flow
• Increases amplitude and duration of contractions
• Leads to dilation and effacement of the cervix
• Stimulates smooth muscle associated with lactating breast
• Causes ejection of milk
• Minimal cardiovascular and antidiuretic properties

Pharmacology

• Uterine motility depends on formation of contractile protein actomyosin
• Oxytocin increases intracellular Ca2+
• Activates myosin's light chain kinase
• Has specific receptors in the muscle lining of the uterus
• Receptor concentration increases greatly during pregnancy
• Reaches maximum in early labor at term

Dosage & Administration

• Given by intravenous infusion under adequate control
• 1-5 IU added to 500 ml of infusion fluid
• Start at 1 mU per minute
• Dosage can be doubled every 30-45 minutes
• Threshold is generally below 10 mU per minute
• Intramuscular administration may lead to irregular response
• Maximum dosage for intramuscular administration

Interaction

• Severe hypertension reported with prophylactic vasoconstrictor
• Cyclopropane anesthesia may modify cardiovascular effects
• Maternal sinus bradycardia with abnormal atrioventricular rhythms noted

Contraindications

• Cephalo-pelvic disproportion
• Abnormal position of the child or skull
• Overdistention of the inferior uterine segment
• Severe toxaemia
• Hypertonic uterine dysfunction
• Foetal distress without imminent delivery
• Cord presentation and prolapse
• Total placenta previa
• Vasa praevia

Side Effects

• Hypersensitivity may result in uterine hypertonicity
• Possibility of increased blood loss and afbrinigenemia
• Severe water intoxication with convulsions and coma
• Nausea, vomiting, haemorrhage, cardiac arrhythmias, anaphylactic reaction
• Increased incidence of icterus neonatorum

Pregnancy & Lactation

• Pregnancy category C
• Excretion in human milk not known

Precautions & Warnings

• Uterine sensitivity may vary widely
• Smallest effective dose must be determined for each patient
• Use only when adequate medical supervision provided
• Fetal heart rate and maternal blood pressure should be determined
• Use with care if scars of the uterus and cervix uteri exist

Overdose Effects

• Excess may cause violent uterine contractions
• Leading to fetal bradycardia and arrhythmias
• Extensive laceration of the soft tissues
• Uterine rupture
• Treatment consists of immediate discontinuation of the infusion and induction of tocolysis

Therapeutic Class

• Drugs acting on the Uterus

Reconstitution

• Potency for at least 24 hours when diluted with specific infusion fluids
• Can be injected directly into the infusion line without precipitation of the ingredients
• 24-hours stability not established for certain fluids

Storage Conditions

• Store in between 2 to 8°C
• In dark and frost free place
• Keep out of the reach of children

Related Brands

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