Carbestop250 mcg/ml

Carbestop is a synthetic prostaglandin F2-alpha analogue (oxytocic agent) used in hospital/obstetric settings under specialist supervision for the following indications:

Established / FDA-approved uses

• Postpartum hemorrhage due to uterine atony: Treatment of refractory postpartum bleeding caused by uterine atony that has not responded to conventional management (e.g., oxytocin, uterine massage, or ergot alkaloids).
• Second-trimester pregnancy termination: Used to induce abortion between the 13th and 20th week of gestation, including as an adjunct when other methods have failed (e.g., missed abortion, ruptured membranes with inadequate uterine activity, or intra-amniotic instillation failure).

Off-label / adjunct use

• Carbestop is sometimes used off-label as an adjunct uterotonic in the prevention or management of severe postpartum hemorrhage refractory to first-line agents during cesarean or vaginal delivery, at the discretion of the treating obstetrician.

Carbestop is administered only by, or under the direct supervision of, clinicians experienced in managing obstetric hemorrhage or pregnancy termination in a monitored hospital setting. It is not intended for outpatient or self-administered use.

Each mL of injectable solution contains Carboprost Tromethamine equivalent to 250 micrograms (mcg) of carboprost, together with tromethamine as a buffering agent, sodium chloride, and benzyl alcohol as a preservative, in water for injection.

Carbestop is the tromethamine (tris(hydroxymethyl)aminomethane) salt of carboprost, a synthetic analogue of naturally occurring prostaglandin F2-alpha (PGF2α). It is supplied as a sterile injectable solution intended for intramuscular administration in emergency obstetric care.

Carbestop was developed to provide a longer duration of uterotonic action than natural prostaglandin F2-alpha, making it useful in situations of severe, refractory uterine atony and in second-trimester pregnancy termination.

Carbestop belongs to the prostaglandin (PGF2α analogue) / oxytocic (uterotonic) agent class of drugs, used specifically for control of obstetric hemorrhage and induction of uterine contractions.

Carboprost Tromethamine stimulates myometrial contractions in the gravid and postpartum uterus similar to labor contractions. Administered intramuscularly, it produces sustained rhythmic uterine contractions that:

• Compress uterine blood vessels at the placental implantation site, producing hemostasis in postpartum hemorrhage due to uterine atony.
• Facilitate expulsion of uterine contents when used for second-trimester pregnancy termination.

As a prostaglandin F2-alpha analogue, Carboprost Tromethamine also has systemic smooth-muscle effects outside the uterus, which account for its characteristic gastrointestinal, respiratory (bronchoconstrictive), and cardiovascular side effects (see Side Effects).

Carbestop is given by deep intramuscular injection only, administered by or under the direct supervision of a physician experienced in obstetric care. It must not be given intravenously. Injection sites should be rotated if repeat doses are required. Carbestop is not intended for self-administration or outpatient use.

Other oxytocic agents: Carbestop may augment the activity of other oxytocic agents (e.g., oxytocin, ergot alkaloids). Concurrent use of Carbestop with other oxytocic agents is not recommended because of the risk of excessive uterine contraction.

No other well-established, clinically significant drug-drug interactions have been established for Carbestop; theoretical interactions with other prostaglandin-active or bronchospasm-inducing agents should be considered on clinical judgment by the treating physician.

Side effects of Carbestop are common and relate to its systemic prostaglandin activity. The most frequently reported effects include:

Gastrointestinal (most common)

• Vomiting (in approximately two-thirds of patients)
• Nausea (approximately one-third of patients)
• Diarrhea, hiccough, gagging

General/systemic

• Transient fever and chills
• Flushing, headache, dizziness
• Muscle pain, weakness

Cardiorespiratory

• Transient hypertension
• Bronchospasm (more likely in patients with asthma or reactive airway disease)

Rare but serious

• Uterine rupture or perforation
• Anaphylactic reaction, angioedema
• Pulmonary edema, septic shock (rare, reported in postmarketing surveillance)

Because drug-induced fever is common with Carbestop, clinicians should distinguish it from infection-related fever (e.g., endometritis) in the postpartum setting.

Carbestop is itself used within obstetric care — for control of postpartum hemorrhage after delivery and for induction of second-trimester abortion — so its "pregnancy" considerations differ from typical medicines. When used for pregnancy termination, Carbestop produces uterine contractions that can affect the fetus; it is not intended to be used to sustain an ongoing pregnancy.

Animal reproduction studies have shown embryotoxic effects at high doses, though no clear teratogenic pattern has been established; any dose producing increased uterine tone could pose risk to a fetus, which is consistent with the drug's intended abortifacient use in the appropriate indication.

Lactation: Data on the excretion of Carbestop into human breast milk are limited. As Carbestop is typically given as a short course immediately postpartum for control of hemorrhage, it should be used only if clearly needed, with the potential benefit weighed against potential risk to the breastfeeding infant; a physician should be consulted regarding breastfeeding timing after administration.

• Carbestop must be administered only in a hospital or equivalent monitored obstetric setting by clinicians experienced in managing obstetric hemorrhage or pregnancy termination — it is not an outpatient or self-administered medicine.
• Use with caution in patients with asthma or reactive airway disease, as prostaglandin F2-alpha analogues can precipitate bronchospasm.
• Use with caution in patients with a history of hypertension, cardiovascular disease, anemia, diabetes, epilepsy, or a scarred uterus (e.g., prior cesarean section).
• Active cardiac, pulmonary, renal, or hepatic disease requires careful individualized risk-benefit assessment before use (see Contraindications).
• Continuous monitoring of vital signs (blood pressure, pulse, temperature), vaginal bleeding, and uterine tone is essential during and after administration, given the emergency nature of the postpartum hemorrhage indication and the systemic effects of the drug.
• Significant gastrointestinal effects (nausea, vomiting, diarrhea) are common; premedication or concurrent treatment with antiemetic and antidiarrheal agents may be used per clinical protocol.
• Drug-induced transient fever should be distinguished from infection-related fever (e.g., endometritis) in the postpartum setting.
• When used for pregnancy termination, incomplete abortion may occur, and the cervix and uterus should be examined afterward for possible trauma; an alternative method of completing the abortion should be available if termination fails.
• The formulation contains benzyl alcohol as a preservative; caution is advised as benzyl alcohol has been associated with serious adverse effects in premature/low-birth-weight neonates when given in high cumulative doses to neonates directly (not applicable to the mother-only intramuscular use of Carbestop, but relevant to overall clinical awareness).

Overdosage with Carbestop may result in excessive uterine contraction (which can cause uterine rupture), exaggerated gastrointestinal effects (severe vomiting, diarrhea), marked hypertension, bronchospasm, or other intensified systemic prostaglandin effects.

There is no specific antidote for Carbestop overdose. Any suspected overdose should be treated as a medical emergency — stop administration immediately and seek immediate medical attention or contact emergency services; management is supportive and symptomatic, guided by the treating physician based on the patient's clinical status.

Store Carbestop injection in a refrigerator at 2°C to 8°C (36°F to 46°F), protected from light. Do not freeze. Keep out of reach of children. Discard any unused portion; use only clear solution from an intact, undamaged ampule.

Renal, hepatic, cardiac, or pulmonary impairment: Active disease in these systems requires careful individualized risk-benefit assessment before Carbestop is used, given its systemic prostaglandin effects (see Contraindications and Precautions).

Asthma/reactive airway disease: Use with caution due to the risk of prostaglandin-induced bronchospasm.

Elderly: Carbestop is used exclusively in women of reproductive age in the obstetric setting; it has no established use in elderly patients.

Pediatric patients: See Pediatric Uses.

Carbestop is used for a short, defined acute-care episode rather than as ongoing therapy. For postpartum hemorrhage, treatment continues only until bleeding is controlled, up to a maximum of 8 doses (2 mg total). For second-trimester pregnancy termination, repeat dosing should not continue for more than 2 consecutive days, up to a maximum total dose of 12 mg. Continued need for Carbestop beyond these limits should prompt reassessment and consideration of alternative management by the treating physician.

Carboprost Tromethamine belongs to the following drug classes: Prostaglandins (PGF2α analogues); Oxytocics; Uterotonic agents.

Carboprost Tromethamine acts as a synthetic analogue of prostaglandin F2-alpha, binding to prostaglandin F (FP) receptors on myometrial smooth muscle. This stimulates strong, sustained rhythmic uterine contractions similar to those of labor. In postpartum hemorrhage, these contractions compress the blood vessels at the placental implantation site, producing hemostasis. In second-trimester pregnancy termination, the sustained contractions promote effacement, dilation, and expulsion of uterine contents.

Carbestop is not indicated for use in pediatric patients. It is used exclusively in adult women of reproductive age for obstetric indications (control of postpartum hemorrhage and second-trimester pregnancy termination). Safety and effectiveness of Carbestop in pediatric patients have not been established.