ERGOSTAT
Clinical safety rating: caution
Comprehensive clinical and safety monograph for ERGOSTAT (ERGOSTAT).
Ergostat (ergotamine) is a serotonin (5-HT) receptor agonist, specifically at 5-HT1B and 5-HT1D receptors, leading to cranial vasoconstriction and inhibition of neurogenic inflammation. It also has partial agonist/antagonist activity at alpha-adrenergic receptors.
| Metabolism | Primarily hepatic via CYP3A4. Undergoes extensive first-pass metabolism. |
| Excretion | Primarily hepatic (biliary-fecal) elimination: ~90% of a dose is excreted in feces as metabolites; renal excretion accounts for <5% unchanged drug. |
| Half-life | Terminal half-life is 2–3 hours (intravenous) and 2–4 hours (oral). Short half-life necessitates frequent dosing; duration of action limited to 2–4 hours. |
| Protein binding | ~65% bound to plasma albumin. Metabolites are less extensively bound. |
| Volume of Distribution | Approximately 0.2–0.3 L/kg, indicating primarily extracellular and peripheral tissue distribution with limited CNS penetration. |
| Bioavailability | Oral: ~10–20% (extensive first-pass metabolism); Sublingual: ~50–60% (avoids portal circulation); Rectal: ~30–40% (variable). |
| Onset of Action | Oral: 10–20 minutes; Sublingual: 5–10 minutes; Rectal: 10–15 minutes; Intravenous: immediate (within 1 minute). |
| Duration of Action | Oral/sublingual/rectal: 2–4 hours (clinical effect wanes after 3 hours). Intravenous: 0.5–2 hours (short-lived, used for acute emergencies). |
0.2 mg intramuscularly or intravenously every 2-4 hours for maximum 5 doses; not to exceed 1 mg total dose.
| Dosage form | TABLET |
| Renal impairment | No specific adjustment; use with caution in severe renal impairment (GFR <30 mL/min) due to potential accumulation. |
| Liver impairment | Child-Pugh Class A: no adjustment; Child-Pugh Class B: reduce dose by 50%; Child-Pugh Class C: avoid use. |
| Pediatric use | Intravenous: 0.1 mg/m² body surface area every 2-4 hours, maximum 0.5 mg total; intramuscular: 0.2 mg every 2-4 hours, maximum 1 mg. |
| Geriatric use | Start at 0.1 mg intramuscularly or intravenously; monitor for hypertension with higher doses. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Comprehensive clinical and safety monograph for ERGOSTAT (ERGOSTAT).
| Breastfeeding | Ergonovine is excreted into breast milk. The M/P ratio is not well established, but small amounts are detectable. It may cause adverse effects in the nursing infant, including vomiting, diarrhea, and transient hypertension. Because of the risk of ergotism in the infant, breastfeeding is generally not recommended during therapy. A decision should be made to discontinue breastfeeding or discontinue the drug, considering the importance of the drug to the mother. |
| Teratogenic Risk | Ergostat (ergonovine) is contraindicated in pregnancy due to its potent uterotonic effects, which can cause uterine tetany, fetal hypoxia, and placental abruption. It is classified as FDA Pregnancy Category X. Use in the first trimester may increase the risk of spontaneous abortion; in the second and third trimesters, it can precipitate preterm labor and fetal distress. There is no evidence of structural teratogenicity from direct drug effects, but the potential for ischemic injury to the fetus due to uterine hyperstimulation exists. |
■ FDA Black Box Warning
Concomitant use with strong CYP3A4 inhibitors (e.g., protease inhibitors, macrolide antibiotics, azole antifungals) can lead to serious and/or life-threatening peripheral ischemia and vasospasm. Avoid coadministration.
| Serious Effects |
["Concurrent use of potent CYP3A4 inhibitors (e.g., boceprevir, clarithromycin, ketoconazole, ritonavir)"]
| Precautions | ["Risk of ischemia (peripheral, cerebral, coronary) especially with prolonged use or overdose","Fibrotic complications (cardiac valvulopathy, pulmonary, retroperitoneal fibrosis) with chronic use","Medication overuse headache (MOH) with frequent use"," Avoid in patients with uncontrolled hypertension, coronary artery disease, or peripheral vascular disease","Do not exceed recommended dosage; may cause ergotism"] |
Loading safety data…
| Fetal Monitoring | Maternal monitoring: Continuous blood pressure monitoring (risk of hypertension), heart rate, and uterine activity (tone and contraction frequency). Monitor for signs of ergotism (nausea, vomiting, paresthesias, chest pain). Fetal monitoring: Continuous fetal heart rate monitoring to detect signs of distress (late decelerations, bradycardia) due to reduced uteroplacental blood flow. Assess for vaginal bleeding indicating placental abruption. |
| Fertility Effects | Ergonovine may impair fertility due to its effects on uterine and ovarian blood flow. It can inhibit implantation if used around the time of conception. In men, no direct effects on sperm parameters have been reported, but ergot alkaloids can cause hyperprolactinemia and potentially suppress gonadotropins, though this is more associated with dopamine agonists than ergonovine. Overall, fertility effects are not well studied. |