Interactions

In certain cases, oxytocin can be used in combination with other oxytocics for therapeutic purposes. There is a risk, however, of severe uterine hypertony occurring, with possible uterine rupture or cervical laceration. The concurrent use of dinoprostone, prostaglandin E2 and oxytocin is considered contraindicated; following the removal of the dinoprostone vaginal insert, an interval of at least 30 minutes is recommended prior to the use of another oxytocic agent. These products should be used sequentially only under adequate obstetric supervision.(5)

Adverse cardiovascular effects can develop as a result of concomitant administration of oxytocin with general anesthetics or with spinal or epidural anesthetics, especially in those with preexisting valvular heart disease. Cyclopropane, when administered with or without oxytocin, has been implicated in producing maternal sinus bradycardia, abnormal atrioventricular rhythms, hypotension, and increases in heart rate, cardiac output, and systemic venous return.(6) In addition, halothane decreases uterine responsiveness to oxytocics (e.g., oxytocin, ergonovine, methylergonovine) and, in high doses, can abolish it, increasing the risk of uterine hemorrhage. Halothane is a potent uterine relaxant.(7) It is not clear if other halogenated anesthetics would interact with oxytocics in this manner.

The administration of prophylactic vasopressors with oxytocin can cause severe, persistent hypertension, as the 2 drugs may have a synergistic and additive vasoconstrictive effect. This interaction was noted when oxytocin was given 3—4 hours after prophylactic vasoconstrictor in conjuction with caudal anesthesia. The incidence of such an interaction may be decreased if vasopressors are not administered prior to oxytocin.(6) This interaction can include certain other sympathomimetics such as ephedra, ma huang.

Do not take this medicine with any of the following medications:

Ephedra, Ma Huang
This medicine may also interact with the following medications:

• dinoprostone, prostaglandin E2
• medicines for blood pressure
• medicines used for sleep during surgery
• other medicines to contract the uterus

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.