NESACAINE-MPF
Clinical safety rating: caution
Comprehensive clinical and safety monograph for NESACAINE-MPF (NESACAINE-MPF).
Nesacaine-MPF (chloroprocaine) is an ester-type local anesthetic that stabilizes neuronal membranes by inhibiting sodium ion influx, thereby blocking impulse conduction in nerve fibers.
| Metabolism | Hydrolyzed by plasma pseudocholinesterase (butyrylcholinesterase) to 2-chloro-4-aminobenzoic acid and diethylaminoethanol. |
| Excretion | Renal excretion of metabolites; <10% unchanged drug. Biliary/fecal elimination minor. |
| Half-life | Terminal half-life: 3-4 hours (adults); prolonged in hepatic or renal impairment. |
| Protein binding | 55-70% bound to alpha-1-acid glycoprotein and albumin. |
| Volume of Distribution | Vd: 1.3-1.5 L/kg; indicates extensive tissue distribution. |
| Bioavailability | Not applicable; administered parenterally. Oral bioavailability negligible due to first-pass metabolism. |
| Onset of Action | Epidural: 5-15 min; Caudal: 5-10 min; Peripheral nerve block: 10-20 min. |
| Duration of Action | Epidural: 60-90 min; with epinephrine: 90-120 min. Duration is dose-dependent. |
| Molecular Weight | 234.34 |
1% solution: 2.5-30 mL (25-300 mg) subcutaneously or locally; maximum 30 mL per dose. 2% solution: 1.25-15 mL (25-300 mg) subcutaneously or locally; maximum 15 mL per dose.
| Dosage form | INJECTABLE |
| Renal impairment | No specific adjustment recommended; use with caution in severe renal impairment due to potential metabolite accumulation. |
| Liver impairment | Child-Pugh Class A: no adjustment. Child-Pugh Class B: reduce dose by 50%. Child-Pugh Class C: contraindicated. |
| Pediatric use | Weight-based: 1% solution up to 4.5 mg/kg subcutaneously or locally; 2% solution up to 4.5 mg/kg subcutaneously or locally. Maximum single dose: weight-dependent but not to exceed adult max. |
| Geriatric use | Lower doses (e.g., 50% of standard) due to increased sensitivity and reduced clearance; monitor for CNS and cardiovascular effects. |
| 1st trimester | No well-controlled studies in pregnant women; use only if potential benefit justifies risk to fetus. Lidocaine crosses placenta rapidly; may cause fetal bradycardia. |
| 2nd trimester | Use caution; consider maternal benefit vs fetal risk. Monitor fetal heart rate. |
| 3rd trimester | Use caution near term; may cause fetal CNS depression and neurobehavioral changes. Accumulation possible due to reduced clearance. |
Clinical note
Comprehensive clinical and safety monograph for NESACAINE-MPF (NESACAINE-MPF).
| Placental transfer | Lidocaine crosses the placenta by passive diffusion; fetal/maternal ratio 0.5–0.7. Rapid equilibrium achieved within minutes. |
| Breastfeeding | Lidocaine is excreted into breast milk in small amounts (milk:plasma ratio ~0.4). Oral bioavailability in infants is low; unlikely to cause adverse effects. Monitor infant for drowsiness and poor feeding. |
■ FDA Black Box Warning
Not for use in patients with known hypersensitivity to ester-type local anesthetics or to para-aminobenzoic acid (PABA). Avoid intravascular injection; test dose recommended before administration of full dose for epidural anesthesia.
| Serious Effects |
Hypersensitivity to lidocaine or amide-type anestheticsSevere heart block (sinoatrial, atrioventricular, or intraventricular) without pacemakerSevere hypotension not due to arrhythmiaPorcine allergy (for Nesacaine-MPF only, due to component)
| Precautions | Risk of central nervous system toxicity and cardiotoxicity with inadvertent intravascular injection or overdose. Use with caution in patients with impaired cardiovascular function, hepatic disease, or pseudocholinesterase deficiency. May cause methemoglobinemia; risk increased with concurrent use of oxidizing agents. |
| Food/Dietary | No known food interactions. Avoid heavy meals before spinal anesthesia due to risk of aspiration. Follow preoperative fasting instructions as directed by your healthcare provider (e.g., no solid food for 6-8 hours, clear liquids up to 2 hours before procedure). |
Loading safety data…
| Lactation Rating | L1 (Safe) |
| Teratogenic Risk | Nesacaine-MPF (chloroprocaine) is a local anesthetic. No well-controlled studies in pregnant women. Animal studies have not shown fetal harm. Caution in first trimester. Risk of fetal bradycardia and acidosis if used in paracervical block during second trimester. Third trimester use may cause fetal heart rate changes. |
| Fetal Monitoring | Monitor maternal vital signs, fetal heart rate, and uterine activity. Assess for signs of systemic toxicity (e.g., CNS, cardiovascular). Epidural test dose recommended. Continuously monitor during anesthesia. |
| Fertility Effects | No known adverse effects on human fertility. Animal studies show no impairment of fertility at clinical doses. |
| Clinical Pearls | NESACAINE-MPF is a sterile, preservative-free solution of chloroprocaine hydrochloride 3% used for spinal anesthesia. Onset is rapid (5-10 minutes) with a short duration (30-60 minutes). It is indicated for procedures lasting <1 hour. Avoid in patients with known hypersensitivity to ester-type anesthetics or para-aminobenzoic acid derivatives. Do not use if solution contains precipitates or discoloration. Monitor for hypotension and bradycardia post-administration; preload with IV fluids as needed. Single-dose vial; discard unused portion. |
| Patient Advice | This medication is used to numb a specific area for surgery or procedures. · You may feel a brief burning sensation at the injection site. · You might experience temporary numbness or weakness in your lower body. · Avoid driving or operating heavy machinery until full sensation returns. · Report any signs of allergic reaction: rash, difficulty breathing, or swelling. · Do not rub or scratch the numb area to prevent injury. · This medication is preservative-free; any unused portion must be discarded. |