oxytocin

Therapeutic Classification: hormones

Pharmacologic Classification: oxytocics

IM:

High Alert

IV: Induction of labor in patients with a medical indication for initiation of labor.
IV: Facilitation of threatened abortion.
IV: Postpartum control of bleeding after expulsion of the placenta.
NOT to be used for elective induction of labor.

Stimulates uterine smooth muscle, producing uterine contractions similar to those in spontaneous labor.
Has vasopressor and antidiuretic effects.

Therapeutic effects:

Induction of labor.
Control of postpartum bleeding.

Absorption: IV administration results in complete bioavailability.

Distribution: Widely distributed in extracellular fluid. Small amounts reach fetal circulation.

Metabolism/Excretion: Rapidly metabolized by liver and kidneys. Primarily excreted in urine as metabolites.

Half-Life: 3–9 min.

(↓ in uterine contractions)

ROUTE	ONSET	PEAK	DURATION
IV	immediate	unknown	1 hr
IM	3–5 min	unknown	30–60 min

Contraindicated in:

Hypersensitivity;
Anticipated nonvaginal delivery.

Use Cautiously in:

OB: 1st and 2nd stages of labor; slow infusion over 24 hr has caused water intoxication with seizure and coma or maternal death due to oxytocin's antidiuretic effect.

Maternal adverse reactions are noted for IV use only

CV: maternalhypotension, fetalarrhythmias

F and E: maternalhypochloremia, hyponatremia, water intoxication

GU: maternal↑uterine motility, painful contractions, abruptio placentae, ↓uterine blood flow

Neuro: maternalCOMA, SEIZURES, fetalINTRACRANIAL HEMORRHAGE

Resp: fetalASPHYXIA, hypoxia

Misc: hypersensitivity reactions

Drug-drug:

Severe hypertension may occur if oxytocin follows administration of vasopressors.

Induction/Stimulation of Labor

IV (Adults ): 0.5–1 milliunits/min; ↑ by 1–2 milliunits/min every 30–60 min until desired contraction pattern established; dose may be ↓ after desired frequency of contractions is reached and labor has progressed to 5–6 cm dilation.

Postpartum Hemorrhage

IV (Adults ): 10 units infused at 20–40 milliunits/min.
IM (Adults ): 10 units after delivery of placenta.

Incomplete/Inevitable Abortion

IV (Adults ): 10 units at a rate of 20–40 milliunits/min.

(Generic available)

Solution for injection: 10 units/mL

Assess fetal maturity, presentation, and pelvic adequacy before administering oxytocin for induction of labor.
Assess character, frequency, and duration of uterine contractions; resting uterine tone; and fetal HR frequently throughout administration. If contractions occur <2 min apart and are >50–65 mm Hg on monitor, if they last ≥60–90 sec, or if a significant change in fetal HR develops, stop infusion and turn patient onto the left side to prevent fetal anoxia. Notify health care provider immediately.
Monitor maternal BP and HR frequently and fetal HR continuously throughout administration.
Monitor for signs/symptoms of water intoxication (drowsiness, listlessness, confusion, headache, anuria).

Lab Test Considerations:

Monitor maternal electrolytes. Water retention may result in hypochloremia or hyponatremia.

Do not confuse oxytocin with Oxycontin.
Do not administer oxytocin simultaneously by >1 route.
IM: 10 units (1 mL) of oxytocin can be given after delivery of the placenta.

IV Administration:

Continuous Infusion: Rotate infusion container to ensure thorough mixing. Store solution in refrigerator, but do not freeze.
- Infuse via infusion pump for accurate dose. Oxytocin should be connected via Y-site injection to an IV of 0.9% NaCl for use during adverse reactions.
- Magnesium sulfate should be available if needed for relaxation of myometrium.
- Dose of oxytocin is determined by uterine response.
Y-Site Compatibility:
- acetaminophen
- acyclovir
- allopurinol
- amikacin
- aminocaproic acid
- aminophylline
- amphotericin B liposomal
- anidulafungin
- argatroban
- ascorbic acid
- atracurium
- atropine
- azathioprine
- azithromycin
- aztreonam
- benztropine
- bivalirudin
- bumetanide
- buprenorphine
- butorphanol
- calcium chloride
- calcium gluconate
- caspofungin
- cefazolin
- cefepime
- cefotaxime
- cefotetan
- cefoxitin
- ceftazidime
- ceftriaxone
- cefuroxime
- chloramphenicol
- chlorothiazide
- ciprofloxacin
- cisatracurium
- clindamycin
- cyclophosphamide
- cyclosporine
- daptomycin
- dexamethasone
- dexmedetomidine
- digoxin
- diltiazem
- diphenhydramine
- dobutamine
- dopamine
- doxycycline
- droperidol
- enalaprilat
- ephedrine
- epinephrine
- epoetin alfa
- eptifibatide
- ertapenem
- erythromycin
- esmolol
- famotidine
- fentanyl
- fluconazole
- folic acid
- foscarnet
- fosphenytoin
- furosemide
- ganciclovir
- gentamicin
- glycopyrrolate
- granisetron
- heparin
- hydrocortisone
- hydromorphone
- imipenem/cilastatin
- isoproterenol
- ketamine
- ketorolac
- labetalol
- leucovorin
- levofloxacin
- lidocaine
- linezolid
- lorazepam
- magnesium sulfate
- mannitol
- meperidine
- meropenem
- methadone
- methylprednisolone
- metoclopramide
- metoprolol
- metronidazole
- midazolam
- milrinone
- minocycline
- morphine
- moxifloxacin
- multivitamins
- mycophenolate
- nafcillin
- nalbuphine
- naloxone
- nicardipine
- nitroglycerin
- nitroprusside
- norepinephrine
- ondansetron
- oxacillin
- palonosetron
- pamidronate
- papaverine
- penicillin G
- pentamidine
- pentobarbital
- phenobarbital
- phentolamine
- phenylephrine
- phytonadione
- piperacillin/tazobactam
- potassium acetate
- potassium chloride
- potassium phosphates
- procainamide
- prochlorperazine
- promethazine
- propranolol
- protamine
- pyridoxine
- sodium acetate
- sodium bicarbonate
- sodium phosphates
- succinylcholine
- sufentanil
- tacrolimus
- theophylline
- thiamine
- tigecycline
- tirofiban
- tobramycin
- vancomycin
- vasopressin
- verapamil
- voriconazole
- zidovudine
- zoledronic acid
Y-Site Incompatibility:
- dantrolene
- diazepam
- dimenhydrinate
- indomethacin
- methohexital
- phenytoin
- remifentanil
- trimethoprim/sulfamethoxazole

Explain purpose and side effects of medication. Advise patient to read Patient Information before starting therapy.
Advise patient to notify health care provider of all Rx or OTC medications, vitamins, or herbal products being taken and to consult health care provider before taking other medications.
Advise patient to expect contractions similar to menstrual cramps after administration has started.

Induction of labor.
Control of postpartum bleeding.

section name header

Pronunciation ⬇

Classifications ⬆ ⬇

Indications ⬆ ⬇

Action ⬆ ⬇

Pharmacokinetics ⬆ ⬇

Time/Action Profile ⬆ ⬇

Contraind./Precautions ⬆ ⬇

Adv. Reactions/Side Effects ⬆ ⬇

Interactions ⬆ ⬇

Route/Dosage ⬆ ⬇

Availability ⬆ ⬇

Assessment ⬆ ⬇

Implementation ⬆ ⬇

Patient/Family Teaching ⬆ ⬇

Evaluation/Desired Outcomes ⬆ ⬇

US Brand Names ⬆