Methergine

Methergine,

trademark for an oxytocic (methylergonovine maleate).

---

methylergonovine maleate

Methergine

Pharmacologic class: Ergot alkaloid

Therapeutic class: Oxytocic

Pregnancy risk category C

Action

Directly stimulates vascular smooth-muscle contractions in uterus and cervix and decreases bleeding after delivery

Availability

Injection: 0.2 mg/ml

Tablets: 0.2 mg

⊘Indications and dosages

➣ Prevention and treatment of postpartum hemorrhage

Adults: 0.2 mg I.M.; repeat q 2 to 4 hours as needed to a total of five doses. In emergencies, 0.2 mg I.V. over 1 minute. After initial I.M. or I.V. dose, 0.2 mg P.O. q 6 to 8 hours for 2 to 7 days; decrease dosage if cramping occurs.

Contraindications

• Hypersensitivity to drug
• Hypertension
• Toxemia
• Pregnancy (except during third stage of labor)

Precautions

Use cautiously in:
• severe hepatic or renal disease, vascular disease, jaundice, sepsis
• patients in second stage of labor.

Administration

• Be aware that drug isn't routinely given I.V. because of risk of severe hypertension and cerebrovascular accident (CVA). Monitor blood pressure and uterine contractions during administration.
• If I.V. use is necessary, give dose over 1 minute. Dose may be diluted in 5 ml of 0.9% sodium chloride injection.
• Be aware that prolonged therapy should be avoided because of ergotism risk.

Route	Onset	Peak	Duration
P.O.	5-10 min	30 min	3 hr
I.V.	Immediate	Unknown	45 min
I.M.	2-5 min	Unknown	3 hr

Adverse reactions

CNS: dizziness, headache, hallucination, seizures, CVA (with I.V. use)

CV: hypertension, hypotension, transient chest pain, palpitations, thrombophlebitis

EENT: tinnitus, nasal congestion

GI: nausea, vomiting, diarrhea

GU: hematuria

Musculoskeletal: leg cramps

Respiratory: dyspnea

Skin: diaphoresis, rash, allergic reactions

Other: foul taste

Interactions

Drug-drug. Dopamine, ergot alkaloids, oxytocin, regional anesthetics, vasoconstrictors: excessive vasoconstriction

Drug-diagnostic tests. Prolactin: increased level

Patient monitoring

☞ Know that if used during third stage of labor, drug increases risk of hemorrhage and infection.
• When giving I.V., closely monitor blood pressure, pulse, uterine contractions, and bleeding.
• Monitor patient for adverse effects.

Patient teaching

• Inform patient and family of reason for using drug, and provide reassurance.
• Tell patient drug may cause nausea, vomiting, dizziness, increased blood pressure, headache, ringing in ears, chest pain, or shortness of breath. Advise her to report severe or troublesome symptoms.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs and tests mentioned above.