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METHYLERGONOVINE MALEATE

Medical Diagnosis and Drugs, Medications
METHYLERGONOVINE MALEATe
(meth-ill-er-goe-noe'veen)
Methergine
Classifications: adrenergic antagonist; ergot alkaloid; oxytocic;
Therapeutic: ergot alkaloid; oxytocic
Prototype: Ergotamine
Pregnancy Category: C

Availability

0.2 mg tablet; 0.2 mg/mL injections

Action

Ergot alkaloid that induces rapid, sustained tetanic uterine contraction that shortens third stage of labor and reduces blood loss.

Therapeutic Effect

Administered after delivery of the placenta. It minimizes the risk of postpartal hemorrhage.

Uses

Routine management after delivery of placenta and for postpartum atony, subinvolution, and hemorrhage. With full obstetric supervision, may be used during second stage of labor.

Contraindications

Hypersensitivity to ergot preparations; induction of labor; use prior to delivery of placenta; threatened spontaneous abortion; prolonged use; uterine sepsis; hypertension; toxemia; angina; arteriosclerosis; CAD; dysfunctional uterine bleeding; eclampsia; hypertension; MI; neonates; PVD; preeclampsia; Raynaud's disease; sepsis; stroke; thromboangiitis obliterans; thrombophlebitis; pregnancy (category C).

Cautious Use

Diabetes mellitus; hepatic disease; migraine headaches; renal failure, renal impairment; pulmonary disease; lactation.

Route & Dosage

Postpartum Hemorrhage
Adult: PO 0.2 q6–8h x 2–7 d IM/IV 0.2 mg q2–4h (max: 5 doses)

Administration

  • Use parenteral routes only in emergencies.
Oral
  • Note: Dosing should not exceed 1 wk.
Intravenous

PREPARE: Direct: Give undiluted or diluted in 5 mL of NS.  

ADMINISTER: Direct: Give 0.2 mg or fraction thereof over 60 sec.  

  • Do not use ampules containing discolored solution or visible particles.
  • Store at 15°–30° C (59°–86° F) unless otherwise directed. Protect from light.

Adverse Effects (≥1%)

GI: Nausea, vomiting (especially with IV doses). CV: Severe hypertensive episodes, bradycardia. Body as a Whole: Allergic phenomena including shock, ergotism.

Interactions

Drug: parenteral sympathomimetics, other ergot alkaloids, triptans add to pressor effects and carry risk of hypertension; protease inhibitors, itraconazole may increase the risk of toxicity.

Pharmacokinetics

Absorption: Readily from GI tract. Onset: 5–15 min PO; 2–5 min IM; immediate IV. Duration: 3 or more h PO; 3 h IM; 45 min IV. Distribution: Distributed into breast milk. Metabolism: Slowly in liver. Elimination: Mainly in feces, small amount in urine. Half-Life: 0.5–2 h.

Nursing Implications

Assessment & Drug Effects

  • Monitor vital signs (particularly BP) and uterine response during and after parenteral administration of methylergonovine until partum period is stabilized (about 1–2 h).
  • Notify physician if BP suddenly increases or if there are frequent periods of uterine relaxation.

Patient & Family Education

  • Report severe cramping for increased bleeding.
  • Report any of the following: Cold or numb fingers or toes, nausea or vomiting, chest or muscle pain.

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug

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