Carboprost

What it is used for

Carboprost tromethamine injection, USP is indicated for aborting pregnancy between the 13th and 20th weeks of gestation as calculated from the first day of the last normal menstrual period and in the following conditions related to second trimester abortion:

1. Failure of expulsion of the fetus during the course of treatment by another method;

2. Premature rupture of membranes in intrauterine methods with loss of drug and insufficient or absent uterine activity;

3. Requirement of a repeat intrauterine instillation of drug for expulsion of the fetus;

4. Inadvertent or spontaneous rupture of membranes in the presence of a previable fetus and absence of adequate activity for expulsion.

Carboprost tromethamine injection is indicated for the treatment of postpartum hemorrhage due to uterine atony which has not responded to conventional methods of management. Prior treatment should include the use of intravenously administered oxytocin, manipulative techniques such as uterine massage and, unless contraindicated, intramuscular ergot preparations.

Studies have shown that in such cases, the use of carboprost tromethamine injection has resulted in satisfactory control of hemorrhage, although it is unclear whether or not ongoing or delayed effects of previously administered ecbolic agents have contributed to the outcome. In a high proportion of cases, carboprost tromethamine injection used in this manner has resulted in the cessation of life threatening bleeding and the avoidance of emergency surgical intervention.

An initial dose of 1 mL of carboprost tromethamine injection sterile solution (containing the equivalent of 250 micrograms of carboprost) is to be administered deep in the muscle. Subsequent doses of 250 micrograms should be administered at 1½ to 3½ hour intervals depending on uterine response.

An optional test dose of 100 micrograms (0.4 mL) may be administered initially. The dose may be increased to 500 micrograms (2 mL) if uterine contractility is judged to be inadequate after several doses of 250 micrograms (1 mL).

The total dose administered of carboprost tromethamine should not exceed 12 milligrams and continuous administration of the drug for more than two days is not recommended.

Side effects, and when to stop

The adverse effects of carboprost tromethamine sterile solution are generally transient and reversible when therapy ends. The most frequent adverse reactions observed are related to its contractile effect on smooth muscle.

In patients studied, approximately two-thirds experienced vomiting and diarrhea, approximately one-third had nausea, one-eighth had a temperature increase greater than 2° F, and one-fourteenth experienced flushing.

The pretreatment or concurrent administration of antiemetic and antidiarrheal drugs decreases considerably the very high incidence of gastrointestinal effects common with all prostaglandins used for abortion. Their use should be considered an integral part of the management of patients undergoing abortion with carboprost tromethamine.

Of those patients experiencing a temperature elevation, approximately one-sixteenth had a clinical diagnosis of endometritis. The remaining temperature elevations returned to normal within several hours after the last injection.

Adverse effects observed during the use of carboprost tromethamine injection for abortion and for hemorrhage, not all of which are clearly drug related, in decreasing order of frequency include:

The most common complications when carboprost tromethamine injection was utilized for abortion requiring additional treatment after discharge from the hospital were endometritis, retained placental fragments, and excessive uterine bleeding, occurring in about one in every 50 patients.

Post-marketing experience:

Hypersensitivity reactions (e.g. Anaphylactic reaction, Anaphylactic shock, Anaphylactoid reaction, Angioedema).

To report SUSPECTED ADVERSE REACTIONS, contact Dr. Reddy's Laboratories Inc., at 1-888-375-3784, or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch

Who should not take it

1. Hypersensitivity (including anaphylaxis and angioedema) to carboprost tromethamine injection sterile solution

2. Acute pelvic inflammatory disease

3. Patients with active cardiac, pulmonary, renal or hepatic disease

Carboprost tromethamine does not appear to directly affect the fetoplacental unit. Therefore, the possibility does exist that the previable fetus aborted by carboprost tromethamine could exhibit transient life signs. Carboprost tromethamine is not indicated if the fetus in utero has reached the stage of viability. Carboprost tromethamine injection should not be considered a feticidal agent.

Evidence from animal studies has suggested that certain other prostaglandins have some teratogenic potential. Although these studies do not indicate that carboprost tromethamine injection is teratogenic, any pregnancy termination with carboprost tromethamine injection that fails should be completed by some other means.

This product contains benzyl alcohol. Benzyl alcohol has been reported to be associated with a fatal "Gasping Syndrome" in premature infants.

Other medicines and interactions

Carboprost tromethamine may augment the activity of other oxytocic agents. Concomitant use with other oxytocic agents is not recommended.

General

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 carboprost tromethamine injection sterile solution can cause similar bone effects.

In patients with a history of asthma, hypo- or hypertension, cardiovascular, renal, or hepatic disease, anemia, jaundice, diabetes, or epilepsy, carboprost tromethamine should be used cautiously.

As with any oxytocic agent, carboprost tromethamine should be used with caution in patients with compromised (scarred) uteri.

Abortion

As with spontaneous abortion, a process which is sometimes incomplete, abortion induced by carboprost tromethamine may be expected to be incomplete in about 20% of cases.

Although the incidence of cervical trauma is extremely small, the cervix should always be carefully examined immediately post-abortion.

Use of carboprost tromethamine is associated with transient pyrexia that may be due to its effect on hypothalamic thermoregulation. Temperature elevations exceeding 2° F (1.1° C) were observed in approximately one-eighth of the patients who received the recommended dosage regimen. In all cases, temperature returned to normal when therapy ended. Differentiation of post-abortion endometritis from drug-induced temperature elevations is difficult, but with increasing clinical experience, the distinctions become more obvious and are summarized below:

Postpartum Hemorrhage

Increased blood pressure. In the postpartum hemorrhage series, 5/115 (4%) of patients had an increase of blood pressure reported as a side effect. The degree of hypertension was moderate and it is not certain as to whether this was in fact due to a direct effect of carboprost tromethamine or a return to a status of pregnancy associated hypertension manifest by the correction of hypovolemic shock. In any event the cases reported did not require specific therapy for the elevated blood pressure. Use in patients with chorioamnionitis. During the clinical trials with carboprost tromethamine, chorioamnionitis was identified as a complication contributing to postpartum uterine atony and hemorrhage in 8/115 (7%) of cases, 3 of which failed to respond to carboprost tromethamine. This complication during labor may have an inhibitory effect on the uterine response to carboprost tromethamine similar to what has been reported for other oxytocic agents. 1

1 Duff, Sanders, and Gibbs; The course of labor in term patients with chorioamnionitis; Am. J. Obstet. Gynecol.; vol. 147, no. 4, October 15, 1983 pp 391–395.

2. For Refractory Postpartum Uterine Bleeding:

An initial dose of 250 micrograms of carboprost tromethamine injection sterile solution (1 mL of carboprost tromethamine injection) is to be given deep, intramuscularly. In clinical trials it was found that the majority of successful cases (73%) responded to single injections. In some selected cases, however, multiple dosing at intervals of 15 to 90 minutes was carried out with successful outcome. The need for additional injections and the interval at which these should be given can be determined only by the attending physicians as dictated by the course of clinical events. The total dose of carboprost tromethamine injection should not exceed 2 milligrams (8 doses).

Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit.