Dinoprostone, as with other potent oxytocic agents, should be used only with strict adherence to recommended dosages. Dinoprostone should be used by medically trained personnel in a hospital which can provide immediate intensive care and acute surgical facilities.
Dinoprostone does not appear to directly affect the fetoplacental unit. Therefore, the possibility does exist that the previable fetus aborted by dinoprostone could exhibit transient life signs. Dinoprostone is not indicated if the fetus in utero has reached the stage of viability. Dinoprostone should not be considered a feticidal agent.
Evidence from animal studies has suggested that certain prostaglandins may have some teratogenic potential. Therefore, any failed pregnancy termination with dinoprostone should be completed by some other means.
PROSTIN E2 Vaginal Suppository should not be used for extemporaneous preparation of any other dosage form.
Neither the PROSTIN E2 Vaginal Suppository, as dispensed nor any extemporaneous formulation made from the PROSTIN E2 Vaginal Suppository should be used for cervical ripening or other indication in the patient with term pregnancy.
There have been post-marketing reports of serious and life-threatening hypersensitivity reactions including anaphylaxis and angioedema with PROSTIN E2 Vaginal Suppository (dinoprostone). Onset of these reported reactions occurred within minutes to hours after initiation with PROSTIN E2 Vaginal Suppository (dinoprostone). If a hypersensitivity reaction is suspected, if possible remove PROSTIN E2 Vaginal Suppository (dinoprostone), assess for other potential causes of the event, and institute symptomatic and supportive therapy, as needed.
1. General precautions
Animal studies lasting several weeks at high doses have shown that prostaglandins of the E and F series can induce proliferation of bone. Such effects have also been noted in newborn infants who have received prostaglandin E1 during prolonged treatment. There is no evidence that short term administration of PROSTIN E2 Vaginal Suppository can cause similar bone effects.
As in spontaneous abortion, where the process is sometimes incomplete, abortion induced by PROSTIN E2 may sometimes be incomplete. In such cases, other measures should be taken to assure complete abortion.
In patients with a history of asthma, hypo-or hypertension, cardiovascular disease, renal disease, hepatic disease, anemia, jaundice, diabetes or history of epilepsy, dinoprostone should be used with caution.
Dinoprostone administered by the vaginal route should be used with caution in the presence of cervicitis, infected endocervical lesions, or acute vaginitis.
As with any oxytocic agent, dinoprostone should be used with caution in patients with compromised (scarred) uteri.
Dinoprostone vaginal therapy is associated with transient pyrexia that may be due to its effect on hypothalamic thermoregulation. In the patients studied, temperature elevations in excess of 2°F (1.1°C) were observed in approximately one-half of the patients on the recommended dosage regimen. In all cases, temperature returned to normal on discontinuation of therapy. Differentiation of post-abortion endometritis from drug-induced temperature elevations is difficult, but with increasing clinical exposure and experience with PGE2 vaginal therapy the distinctions become more obviously apparent and are summarized below:
|Endometritis pyrexia||PGE2 induced pyrexia|
||Within 15–45 minutes of suppository administration.|
||Elevations revert to pretreatment levels within 2–6 hours after discontinuation of therapy or removal of suppository from vagina without any other treatment.|
||Elevation occurs irrespective of any retained tissue.|
||Although the endometrial stroma may be edematous and vascular, there is relative absence of inflammatory reaction.|
||Normal uterine involution not tender.|
In the absence of clinical or bacteriological evidence of intrauterine infection, supportive therapy for drug induced fevers includes the forcing of fluids. As all PGE2-induced fevers have been found to be transient or self-limiting, it is doubtful if any simple empirical measures for temperature reduction are indicated.
2. Laboratory tests
When a pregnancy diagnosed as missed abortion is electively interrupted with intravaginal administration of dinoprostone, confirmation of intrauterine fetal death should be obtained in respect to a negative pregnancy test for chorionic gonadotropic activity (U.C.G. test or equivalent). When a pregnancy with late fetal intrauterine death is interrupted with intravaginal administration of dinoprostone, confirmation of intrauterine fetal death should be obtained prior to treatment.
3. Drug interactions
PROSTIN E2 may augment the activity of other oxytocic drugs. Concomitant use with other oxytocic agents is not recommended.
4. Carcinogenesis, mutagenesis, impairment of fertility
Carcinogenic bioassay studies have not been conducted in animals with PROSTIN E2 due to the limited indications for use and short duration of administration. No evidence of mutagenicity was observed in the Micronucleus Test or Ames Assay.
Animal studies do not indicate that PROSTIN E2 is teratogenic, however, it has been shown to be embryotoxic in rats and rabbits and any dose which produces increased uterine tone could put the embryo or fetus at risk [see WARNINGS].