Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
WIGRETTES vs Ergometrine / Methylergonovine
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Nicotine replacement therapy: binds to nicotinic acetylcholine receptors in the brain, releasing dopamine and providing nicotine to reduce withdrawal symptoms and cravings.
Ergometrine and methylergonovine are ergot alkaloids that act as partial agonists at alpha-adrenergic, dopaminergic, and serotonergic (5-HT2) receptors. Their primary uterotonic effect is mediated by stimulation of 5-HT2 receptors in uterine smooth muscle, leading to sustained contractions and vasoconstriction.
Smoking cessation therapy,Relief of nicotine withdrawal symptoms
Prevention and treatment of postpartum hemorrhage (FDA approved),Uterine atony (FDA approved),Ovarian hyperstimulation syndrome (off-label),Variceal bleeding (off-label),Migraine headache (off-label)
1 mg sublingually as needed for smoking cessation, up to 4 times daily. Maximum daily dose: 4 mg.
0.2 mg intramuscularly or intravenously, repeated every 2-4 hours as needed, up to 5 doses total. Maximum single dose: 0.5 mg. Maximum total dose: 1 mg.
Terminal elimination half-life is 12-15 hours in adults with normal renal function; prolonged to 24-30 hours in moderate renal impairment.
30-120 min (biphasic: initial 10 min, terminal 30-120 min); clinical context: short half-life allows repeated dosing for postpartum hemorrhage but requires monitoring for accumulation
Primarily hepatic via CYP2A6 and CYP2B6; also metabolized by aldehyde oxidase and N-glucuronidation.
Primarily hepatic via CYP3A4; also undergoes first-pass metabolism. Metabolites are excreted in urine and bile.
Renal excretion of unchanged drug accounts for 50-60% of the dose; biliary/fecal elimination accounts for 20-30%; remainder metabolized.
Renal (20% unchanged), biliary/fecal (35% as metabolites and parent compound)
90-95% bound to albumin and alpha-1-acid glycoprotein.
85-90% (primarily to albumin and α1-acid glycoprotein)
Volume of distribution is 0.8-1.2 L/kg, indicating extensive tissue distribution.
0.4-0.6 L/kg; clinical meaning: moderate tissue distribution, consistent with limited extravascular binding
Oral bioavailability is 60-80%; intramuscular bioavailability is 90-100%.
Oral: 20-40% (due to extensive first-pass metabolism); IM: ~80%
No specific dose adjustment required; use with caution in severe renal impairment (Cr Cl <30 m L/min) due to limited data.
No specific guidelines; use with caution in severe renal impairment (GFR <30 m L/min) due to risk of accumulation and hypertensive effects.
Child-Pugh Class A: No adjustment. Child-Pugh Class B: Reduce dose to 1 mg maximum twice daily. Child-Pugh Class C: Avoid use (not recommended).
Child-Pugh Class A: no adjustment. Child-Pugh Class B: reduce dose by 50% or extend interval. Child-Pugh Class C: avoid use.
Not approved for patients under 18 years of age.
0.1-0.2 mg intramuscularly or intravenously every 2-4 hours as needed; maximum single dose 0.2 mg. For postpartum hemorrhage, 0.2 mg IM/IV repeated every 2-4 hours, max 5 doses.
No specific dose adjustment; monitor for adverse effects due to potential age-related decreased renal function.
Use lowest effective dose due to increased sensitivity and higher risk of hypertension and coronary vasospasm; consider 0.1 mg initially and titrate cautiously.
None
Concurrent use with potent CYP3A4 inhibitors (e.g., macrolide antibiotics, protease inhibitors, azole antifungals) may result in acute ergot toxicity (vasospasm, cerebral and peripheral ischemia). Contraindicated in pregnancy for induction of labor due to risk of uterine rupture and fetal harm.
Risk of nicotine toxicity if used while smoking; caution in cardiovascular disease, hypertension, diabetes, hyperthyroidism, pheochromocytoma; may cause allergic reactions including angioedema; pregnancy category D.
May cause hypertension, especially in patients with preeclampsia or hypertension. Use with caution in patients with sepsis, hepatic or renal impairment, coronary artery disease, or peripheral vascular disease. Avoid prolonged use. Monitor uterine tone and bleeding.
Hypersensitivity to nicotine or any component; nonsmokers; immediate post-myocardial infarction period; life-threatening arrhythmias; severe or worsening angina pectoris.
Pregnancy (except for postpartum hemorrhage), hypertension, preeclampsia, eclampsia, coronary artery disease, peripheral vascular disease, Raynaud's phenomenon, sepsis, hypersensitivity to ergot alkaloids, concurrent use of potent CYP3A4 inhibitors.
No known food interactions. Avoid concurrent use of retinoid creams or other exfoliating agents that may increase skin sensitivity.
No known food interactions.
WIGRETTES contains nicotine, which is a known teratogen. First trimester exposure is associated with increased risk of spontaneous abortion, preterm birth, and low birth weight. Second and third trimester exposure can lead to reduced fetal growth, placental complications (e.g., abruption), and potential neurobehavioral effects. The risk is dose-dependent and compounded by maternal smoking.
First trimester: Limited human data; animal studies show embryotoxicity and fetotoxicity at high doses due to uterotonic effects, but no structural malformations. Increased risk of spontaneous abortion from uterine hyperstimulation. Second trimester: Uterotonic effects may cause placental abruption, preterm labor, or fetal hypoxia. Third trimester: Contraindicated due to potent uterotonic activity; can cause uterine tetany, fetal distress, and stillbirth. Avoid during pregnancy unless for postpartum hemorrhage.
Nicotine is excreted into breast milk with a milk-to-plasma ratio of approximately 2.9. Concentrations can exceed maternal serum levels. Nursing infants are at risk for nicotine absorption leading to irritability, sleep disturbances, and reduced milk intake. Breastfeeding is generally discouraged during nicotine replacement therapy; if used, timing of patches should minimize infant exposure (e.g., remove at night).
Ergometrine and methylergonovine are excreted into breast milk in small amounts; M/P ratio estimated at 0.2-0.3. Milk concentrations are low (approximately 1-2% of maternal weight-adjusted dose). The American Academy of Pediatrics considers use compatible with breastfeeding, but may cause ergotism in infants (vomiting, diarrhea, seizures) with prolonged use. Short-term use for postpartum hemorrhage is generally acceptable.
Pregnancy increases nicotine clearance by approximately 60%, potentially reducing efficacy of standard doses. Higher doses of nicotine replacement therapy may be required to achieve therapeutic effect and prevent withdrawal. However, safety of high-dose NRT in pregnancy is not established. Dose should be individualized based on maternal smoking history and withdrawal symptoms.
No dose adjustment required for pregnancy because drug is contraindicated during pregnancy due to uterotonic effects. In postpartum use (which is the approved indication), no pharmacokinetic changes necessitate dose adjustment; normal adult dosing applies (0.2 mg IM/IV for ergometrine, 0.2 mg IM for methylergonovine).
Wigrettes are wax-based hair removal products containing depilatory agents like calcium thioglycolate. For scalp use only; avoid contact with eyes and broken skin. Perform a patch test 24 hours prior to first use. Do not use on irritated or sunburned skin. Overuse may cause chemical burns or allergic contact dermatitis. Duration of application time is critical: typically 5-10 minutes, do not exceed 15 minutes. Remove with a wooden spatula in direction of hair growth. Neutralize residue with water or mild soap.
Administer intramuscularly or intravenously (slow push over 1 minute) for uterine atony; avoid in hypertension, preeclampsia, and sepsis. Store ampules protected from light; discard if discolored. Contraindicated in impaired hepatic or renal function.
Read all directions before use.,Do a patch test on a small area of skin 24 hours before use.,Apply only to clean, dry scalp hair; not for eyebrows, eyelashes, or body hair.,Avoid contact with eyes, nose, and mouth. If contact occurs, rinse with plenty of water.,Do not use on sunburned, broken, or irritated skin.,Set a timer; do not leave on longer than directed (usually 5-10 minutes, max 15 minutes).,Remove product gently with the provided spatula in the direction of hair growth.,Rinse scalp thoroughly with water after removal; do not use soap immediately if irritation occurs.,Do not use more than once every 72 hours.,Store in a cool, dry place away from children.
This medication may cause nausea, vomiting, or headache.,Report severe abdominal pain, chest pain, or difficulty breathing immediately.,Avoid driving or operating machinery if dizziness occurs.,Do not use during pregnancy except for postpartum hemorrhage.,Inform your doctor if you have high blood pressure, heart disease, or are breastfeeding.
No interactions on record
"Coadministration of bromocriptine, a dopamine D2 receptor agonist with vasoconstrictive properties, and ergometrine, an ergot alkaloid that acts as a partial agonist at alpha-adrenergic and serotonin receptors, synergistically increases peripheral vasoconstriction. This additive effect can lead to severe hypertension, myocardial ischemia, cerebral vasospasm, and potentially life-threatening ergotism. Patients may present with headache, chest pain, altered mental status, or peripheral ischemia."
"Nylidrin, a beta-adrenergic agonist, and ergometrine, an ergot alkaloid with vasoconstrictive properties, exhibit a synergistic hypertensive effect. By stimulating beta-2 receptors, nylidrin may cause peripheral vasodilation and reflex tachycardia, while ergometrine induces vasoconstriction via alpha-adrenergic and serotonin receptor activation. This opposing mechanism can lead to unopposed vasoconstriction, potentially resulting in severe hypertension, myocardial ischemia, or stroke."
"Simvastatin, a HMG-CoA reductase inhibitor, may increase the serum concentration of ergometrine, an ergot alkaloid used for postpartum hemorrhage, by inhibiting its metabolism via CYP3A4. This can lead to enhanced vasoconstrictive effects of ergometrine, potentially causing severe hypertension, myocardial ischemia, or peripheral vasospasm. Concomitant use poses a risk of ergotism, manifesting as ischemic complications, and should be approached with caution."
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about WIGRETTES vs Ergometrine / Methylergonovine, answered by our medical review team.
WIGRETTES is a Ergot Alkaloid that works by Nicotine replacement therapy: binds to nicotinic acetylcholine receptors in the brain, releasing dopamine and providing nicotine to reduce withdrawal symptoms and cravings.. Ergometrine / Methylergonovine is a Ergot Alkaloid Uterotonic that works by Ergometrine and methylergonovine are ergot alkaloids that act as partial agonists at alpha-adrenergic, dopaminergic, and serotonergic (5-HT2) receptors. Their primary uterotonic effect is mediated by stimulation of 5-HT2 receptors in uterine smooth muscle, leading to sustained contractions and vasoconstriction.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between WIGRETTES and Ergometrine / Methylergonovine depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of WIGRETTES is: 1 mg sublingually as needed for smoking cessation, up to 4 times daily. Maximum daily dose: 4 mg.. The standard adult dose of Ergometrine / Methylergonovine is: 0.2 mg intramuscularly or intravenously, repeated every 2-4 hours as needed, up to 5 doses total. Maximum single dose: 0.5 mg. Maximum total dose: 1 mg.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between WIGRETTES and Ergometrine / Methylergonovine in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. WIGRETTES is classified as Category C. WIGRETTES contains nicotine, which is a known teratogen. First trimester exposure is associated with increased risk of spontaneous abortion, preterm birth, and low birth weight. Se. Ergometrine / Methylergonovine is classified as Category C. First trimester: Limited human data; animal studies show embryotoxicity and fetotoxicity at high doses due to uterotonic effects, but no structural malformations. Increased risk of. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.