HEAVY SOLUTION NUPERCAINE
Clinical safety rating: caution
Comprehensive clinical and safety monograph for HEAVY SOLUTION NUPERCAINE (HEAVY SOLUTION NUPERCAINE).
Heavy solution nupercaine (dibucaine) is a potent, long-acting amide local anesthetic that stabilizes neuronal membranes by blocking voltage-gated sodium channels, thereby inhibiting the propagation of action potentials and preventing nerve impulse conduction.
| Metabolism | Primarily metabolized in the liver via ester hydrolysis (pseudocholinesterase) and N-dealkylation; exhibits biexponential elimination with a terminal half-life of approximately 2-4 hours. Metabolites are excreted renally. |
| Excretion | Primarily hepatic metabolism to inactive metabolites; renal excretion of unchanged drug accounts for approximately 1-5%. Biliary excretion is minimal (<5%). Total fecal elimination is negligible (<1%). |
| Half-life | Terminal elimination half-life is 2.5-4 hours (mean 3.5 h) in adults. In neonates, half-life is prolonged (up to 8-12 h) due to immature hepatic function. |
| Protein binding | Approximately 95% bound to plasma proteins, primarily alpha1-acid glycoprotein and albumin. |
| Volume of Distribution | Vd is 0.6-1.2 L/kg (mean 0.9 L/kg), indicating moderate tissue distribution. Higher Vd in neonates (1.5-2.0 L/kg). |
| Bioavailability | Not applicable for IV administration (100%). Intrathecal: 100% (direct CNS delivery). Epidural: 60-80% systemic absorption due to vascular uptake. Topical: negligible systemic bioavailability. |
| Onset of Action | Intrathecal: 5-10 minutes for surgical anesthesia. Epidural: 15-20 minutes for analgesia/anesthesia. Topical: 30-60 seconds for corneal anesthesia. |
| Duration of Action | Intrathecal: 2-4 hours of surgical anesthesia; prolonged with epinephrine (3-5 h). Epidural: 1.5-3 hours. Topical corneal: 20-30 minutes. |
| Molecular Weight | 343.46 |
Spinal anesthesia: 0.5-1 mL of 0.5% heavy solution (2.5-5 mg) injected intrathecally; dose depends on level of anesthesia required.
| Dosage form | INJECTABLE |
| Renal impairment | No specific dosage adjustment guidelines; use with caution in renal impairment due to potential for systemic accumulation. |
| Liver impairment | No specific Child-Pugh based adjustments; use with caution in severe hepatic impairment due to decreased metabolism. |
| Pediatric use | Not recommended; safety and efficacy not established. If used, dose should be individualized based on weight and clinical response. |
| Geriatric use | Reduce dose by 20-50% due to increased sensitivity and reduced clearance; monitor closely for hypotension and prolonged block. |
| 1st trimester | Avoid; local anesthetics may cause fetal bradycardia and CNS depression. |
| 2nd trimester | Use only if clearly needed; no well-controlled studies. |
| 3rd trimester | May cause neonatal CNS depression and bradycardia near term. |
Clinical note
Comprehensive clinical and safety monograph for HEAVY SOLUTION NUPERCAINE (HEAVY SOLUTION NUPERCAINE).
| Placental transfer | Cinchocaine crosses the placenta by passive diffusion; degree similar to other amide anesthetics. |
| Breastfeeding | Cinchocaine is excreted into breast milk in small amounts, but risk to nursing infant is considered low at therapeutic doses. Monitor for signs of local anesthetic toxicity (e.g., irritability, drowsiness). |
| Lactation Rating |
■ FDA Black Box Warning
WARNING: RISK OF CARDIAC ARREST AND DEATH WITH INTRAVASCULAR INJECTION. Accidental intravascular injection may result in cardiac arrest or sudden death due to severe cardiotoxicity. Resuscitative equipment and personnel must be immediately available. Use only with continuous monitoring and in settings prepared for emergency resuscitation.
| Serious Effects |
Hypersensitivity to amide anestheticsInfection at injection siteProposed use in caudal anesthesia in children under 2 years
| Precautions | Risk of systemic toxicity from accidental intravascular injection or overdose; monitor vital signs continuously., May cause methemoglobinemia, especially with prolonged use or high doses; treat with methylene blue if symptomatic., Use with caution in patients with hepatic impairment, renal dysfunction, or history of seizures., Elderly and debilitated patients require dose reduction due to increased susceptibility to adverse effects., Avoid use in patients with allergy to amide local anesthetics. |
| Food/Dietary | No specific dietary restrictions. Avoid alcohol for 24 hours post-procedure to reduce risk of hypotension and dizziness. |
Loading safety data…
| L2 (Probably Compatible) |
| Teratogenic Risk | Heavy Solution Nupercaine (dibucaine) is a potent amide local anesthetic. In the first trimester, there is limited human data; animal studies show no consistent teratogenicity. Second and third trimesters: risk of fetal bradycardia and hypoxia due to placental transfer. High doses may cause neonatal CNS depression. Not associated with major malformations at standard doses. |
| Fetal Monitoring | Monitor maternal vital signs, ECG, and level of anesthesia. Fetal heart rate monitoring during administration. Assess for maternal hypotension, seizures, or cardiac arrhythmias. Monitor fetal bradycardia and neonatal depression post-delivery. |
| Fertility Effects | No direct adverse effects on fertility reported in humans. Animal studies show no impairment at clinical doses. |
| Clinical Pearls | Heavy solution Nupercaine (dibucaine) is a long-acting amide local anesthetic used for spinal anesthesia. Its hyperbaric formulation ensures preferential spread to dependent areas. Onset is 5-10 minutes, duration 2-3 hours. Contraindicated in hypotension, hypovolemia, and known allergy. Monitor for high spinal block and hypotension. Avoid epinephrine due to risk of arachnoiditis. Store at room temperature. |
| Patient Advice | You may feel numbness and inability to move legs for several hours after spinal injection. · Remain lying flat for the duration of the block to prevent headache and ensure proper spread. · Report any difficulty breathing, chest tightness, or severe headache immediately. · Avoid driving or operating machinery until full sensation and motor function return. · Do not consume alcohol for at least 24 hours after the procedure. |