Methergin

# Methergin ## Overview - **Classification**: Ergot alkaloid, uterotonic agent. - **Mechanism**: Acts directly on the uterine smooth muscle, causing rapid and sustained tonic contractions. This action compresses blood vessels and reduces postpartum blood loss. ## Primary Indications 1. **Prevention and treatment of postpartum hemorrhage (PPH)**: Due to uterine atony or subinvolution. 2. **Prevention and treatment of hemorrhage following abortion**: Or miscarriage. 3. **Control of uterine bleeding**: In other gynecological procedures. ## Adult Dosing ### Standard Dosing **Prevention/Treatment of Postpartum/Post-Abortion Hemorrhage** - **Dose**: **0.2 mg** - **Frequency**: Every **2-4 hours** as needed. - **Route**: Intramuscular (IM) preferred. - **Duration**: Usually **2-5 doses** IM. **IV Administration (Emergencies Only)** - **Dose**: **0.2 mg** slowly over at least **60 seconds**. - **Frequency**: Single dose; repeat only in life-threatening situations. - **Route**: Intravenous (IV). - **Special consideration**: Avoid rapid IV push due to severe hypertension risk. **Oral Dosing (Maintenance after Initial IM/IV)** - **Dose**: **0.2 mg** - **Frequency**: Every **6-8 hours**. - **Route**: Oral. - **Duration**: For up to **7 days**. ### Dose Adjustments - **Renal Impairment**: Use with **caution**. No specific dose adjustments; monitor for adverse effects. - **Hepatic Impairment**: Use with **caution**. Metabolized by liver; monitor for increased effects. - **Elderly Patients**: Not typically indicated; if used in reproductive age, consider general cardiovascular status. ## Pediatric Dosing ### Neonates (0-28 days) - **Special Notes**: **Not indicated**. No therapeutic use in this age group. ### Infants (1-12 months) - **Special Notes**: **Not indicated**. No therapeutic use in this age group. ### Children (1-12 years) - **Special Notes**: **Not indicated**. No therapeutic use in this age group. ### Adolescents (13-18 years) - **Dose**: As per **adult dosing (0.2 mg)** when clinically indicated (e.g., post-abortion hemorrhage). - **Frequency**: As per adult regimen (e.g., IM **q2-4h** prn). - **Maximum**: **0.2 mg** per dose; total daily dose should not exceed **1 mg** (5 doses). - **Special Notes**: Use only when clear indication for uterine contractility exists. ## Safety Information ### Contraindications - **Absolute**: **Hypertension** (pre-eclampsia, eclampsia, chronic, gestational). - **Absolute**: **Hypersensitivity** to ergot alkaloids. - **Absolute**: **Cardiac disease** (e.g., coronary artery disease). - **Absolute**: **Peripheral vascular disease**. - **Absolute**: **Sepsis**. - **Absolute**: **Concurrent use with potent CYP3A4 inhibitors** (e.g., ritonavir, clarithromycin, ketoconazole). ### Common Adverse Effects - **Very Common (>10%)**: Hypertension (especially IV), nausea, vomiting, abdominal pain/cramps. - **Common (1-10%)**: Headache, dizziness, bradycardia, chest pain, dyspnea, palpitation. - **Serious but Rare**: Myocardial infarction, stroke, seizures, severe anaphylaxis, ergotism. ### Key Drug Interactions - **Potent CYP3A4 Inhibitors (e.g., clarithromycin, ritonavir, ketoconazole)**: Markedly increased methylergonovine levels, risk of severe vasoconstriction/hypertension. **Contraindicated**. - **Other Vasoconstrictors (e.g., dopamine, sumatriptan, ergotamine)**: Synergistic vasoconstriction, risk of severe hypertension. **Avoid concurrent use**. - **Nitrates**: May reduce anti-anginal effect of nitrates. - **Beta-blockers**: May enhance vasoconstriction and increase blood pressure. ## Monitoring & Follow-up - **Before Treatment**: Baseline blood pressure and pulse. Assess history of hypertension, cardiac disease. - **During Treatment**: Frequent blood pressure and pulse monitoring (especially IV: every **5-15 minutes**). Monitor uterine tone and amount of bleeding. - **Clinical Signs**: Watch for elevated BP, headache, chest pain, signs of ergotism (e.g., cold/pale extremities). ## Clinical Pearls - 💡 **Tip 1**: **IM route is preferred** due to a lower risk of severe hypertension compared to IV administration. - 💡 **Tip 2**: If IV administration is essential, dilute and administer **slowly (over at least 60 seconds)** to minimize hypertensive crisis. - 💡 **Tip 3**: **Closely monitor BP** and uterine response to prevent complications. Have antihypertensives readily available for severe hypertension. - 💡 **Tip 4**: Not for routine induction or augmentation of labor; specifically for postpartum/post-abortion hemorrhage. > **⚠️ Important**: This information is for educational purposes only. Always consult current prescribing information, local guidelines, and clinical judgment before prescribing.