Oxytocin (Pitocin ®)
|The authors make no claims of the accuracy of the information contained herein; and these suggested doses and/or guidelines are not a substitute for clinical judgment. Neither GlobalRPh Inc. nor any other party involved in the preparation of this document shall be liable for any special, consequential, or exemplary damages resulting in whole or part from any user's use of or reliance upon this material. PLEASE READ THE DISCLAIMER CAREFULLY BEFORE ACCESSING OR USING THIS SITE. BY ACCESSING OR USING THIS SITE, YOU AGREE TO BE BOUND BY THE TERMS AND CONDITIONS SET FORTH IN THE DISCLAIMER.|
Standard Dilutions [Amount of drug] [Infusion volume] [Infusion rate]
[30 units ] [ 500 ml ] [Titrate]
One milliunit per minute equals 1 ml per hour
[10 to 40units] [1000ml] [Titrate]
Stability / Miscellaneous
The pharmacologic and clinical properties of oxytocin are identical with those of naturally occurring oxytocin principle of the posterior lobe of pituitary. Oxytocin exerts a selective action on the smooth musculature of the uterus, particularly toward the end of pregnancy, during labor, and immediately following delivery. Oxytocin stimulates rhythmic contractions of the uterus, increases the frequency of existing contractions, and raises the tone of the uterine musculature. When given in appropriate doses during pregnancy, oxytocin is capable of eliciting graded increases in uterine motility from a moderate increase in the rate and force of spontaneous motor activity to sustained titanic contraction. The sensitivity of the uterus to oxytocic activity increases progressively throughout pregnancy until term when it is maximal. Oxytocin is distributed throughout the extracellular fluid. Small amounts of this drug probably reach the fetal circulation. Oxytocin has a plasma half-life of about 3 to 5 minutes. Following parenteral administration, uterine response occurs within 3 to 5 minutes and persists for 2 to 3 hours. Its rapid removal from plasma is accomplished largely by the kidney and the liver. Only small amounts oxytocin are excreted in the urine unchanged.
INDICATIONS AND USAGE [top]
Oxytocin is indicated for the initiation or improvement of uterine contractions, where this is desirable and considered suitable for reasons of fetal or maternal concern, in order to achieve early vaginal delivery. It is indicated for (1) induction of labor in patients with a medical indication for the initiation of labor, such as Rh problems, maternal diabetes, preeclampsia at or near term, when delivery is in the best interests of mother and fetus or when membranes are prematurely ruptured and delivery is indicated; (2) stimulation or reinforcement of labor, as in selected cases of uterine inertia; (3) as adjunctive therapy in the management of incomplete or inevitable abortion. In the first trimester, curettage is generally considered primary therapy. In second trimester abortion, oxytocin infusion will often be successful in emptying the uterus. Other means of therapy, however, may be required in such cases.
Oxytocin is indicated to produce uterine contractions during the third stage of labor and to control postpartum bleeding or hemorrhage.
Oxytocin is contraindicated in any of the following conditions:
significant cephalopelvic disproportion;
unfavorable fetal positions or presentations which are undeliverable without conversion prior to delivery, e.g., transverse lies;
in obstetrical emergencies where the benefit-to-risk ratio for either the fetus or the mother favors surgical intervention;
in cases of fetal distress where delivery is not imminent;
hypertonic uterine patterns;
hypersensitivity to the drug.
Prolonged use in uterine inertia or severe toxemia is contraindicated.
Oxytocin should not be used in cases where vaginal delivery is not indicated, such as cord presentation or prolapse, total placenta previa, and vasa previa.
Oxytocin, when given for induction or stimulation of labor, must be administered only by intravenous infusion (drip method) and with adequate medical supervision in a hospital.
The following adverse reactions have been reported in the mother:
Excessive dosage or hypersensitivity to the drug may result in uterine hypertonicity, spasm, tetanic contraction, or rupture of the uterus.
The possibility of increased blood loss and afibrinogenemia should be kept in mind when administering the drug.
Severe water intoxication with convulsions and coma has occurred, associated with a slow oxytocin infusion over a 24-hour period. Maternal death due to oxytocin-induced water intoxication has been reported.
The following adverse reactions have been reported in the fetus or infant:
(Due to induced uterine motility)
(Due to use of oxytocin in the mother)
Overdosage with oxytocin depends essentially on uterine hyperactivity whether or not due to hypersensitivity to this agent. Hyperstimulation with strong (hypertonic) or prolonged (tetanic) contractions, or a resting tone of 15 to 20 mm H2O or more between contractions can lead to tumultuous labor, uterine rupture, cervical and vaginal lacerations, postpartum hemorrhage, utero-placental hypoperfusion, and variable deceleration of fetal heart, fetal hypoxia, hypercapnia, or death. Water intoxication with convulsions, which is caused by the inherent antidiuretic effect of oxytocin, is a serious complication that may occur if large doses (40 to 50 milliunits/minute) are infused for long periods. Management consists of immediate discontinuation of oxytocin and symptomatic and supportive therapy.
Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit.
Dosage of oxytocin is determined by the uterine response. The following dosage information is based upon various regimens and indications in general use.A. Induction or Stimulation of Labor
Intravenous infusion (drip method) is the only acceptable method of administration for the induction or stimulation of labor.
Accurate control of the rate of infusion flow is essential. An infusion pump or other such device and frequent monitoring of strength of contractions and fetal heart rate are necessary for the safe administration of oxytocin for the induction or stimulation of labor. If uterine contractions become too powerful, the infusion can be abruptly stopped, and oxytocic stimulation of the uterine musculature will soon wane.
B. Control of Postpartum Uterine Bleeding
C. Treatment of Incomplete or Inevitable Abortion
Intravenous infusion with physiologic saline solution, 500 mL, or 5% dextrose in physiologic saline solution to which 10 units of oxytocin have been added should be infused at a rate of 20 to 40 drops per minutes.
Source: [package insert]
|The authors make no claims of the accuracy of the information contained herein; and these suggested doses are not a substitute for clinical judgment. Neither GlobalRPh Inc. nor any other party involved in the preparation of this program shall be liable for any special, consequential, or exemplary damages resulting in whole or part from any user's use of or reliance upon this material. PLEASE READ THE DISCLAIMER CAREFULLY BEFORE ACCESSING OR USING THIS SITE. BY ACCESSING OR USING THIS SITE, YOU AGREE TO BE BOUND BY THE TERMS AND CONDITIONS SET FORTH IN THE DISCLAIMER.|