LIDOCAINE HYDROCHLORIDE 0.4% AND DEXTROSE 5% IN PLASTIC CONTAINER
Clinical safety rating: safe
Beta-blockers may increase the risk of lidocaine toxicity Can cause CNS toxicity (seizures) and cardiovascular collapse.
Lidocaine is a amide-type local anesthetic that blocks voltage-gated sodium channels in neuronal membranes, inhibiting the initiation and conduction of nerve impulses. Dextrose provides calories and does not have pharmacological activity.
| Metabolism | Lidocaine is primarily metabolized in the liver via oxidative N-dealkylation (CYP1A2, CYP3A4) to monoethylglycinexylidide (MEGX) and glycinexylidide (GX). Dextrose is metabolized via glycolysis and the citric acid cycle. |
| Excretion | Renal: Approximately 90% of lidocaine is metabolized in the liver, and less than 10% is excreted unchanged in urine. The major metabolites (monoethylglycinexylidide and glycinexylidide) are excreted renally. Biliary/fecal excretion is minimal (<1%). |
| Half-life | Terminal elimination half-life: 1.5–2 hours after a single dose in healthy adults. In patients with hepatic impairment, heart failure, or prolonged infusion, half-life can increase to >3 hours due to reduced clearance. Neonates: 3–6.3 hours. |
| Protein binding | 60–80% bound primarily to alpha-1-acid glycoprotein (AAG). Binding is concentration-dependent and saturable at high doses. In conditions with elevated AAG (e.g., trauma, myocardial infarction), free fraction decreases. |
| Volume of Distribution | Vd: 1.1–1.6 L/kg. Rapid distribution to well-perfused tissues (brain, heart, liver, kidneys). Reflects extensive tissue binding; increased Vd in obesity (due to adipose tissue) and neonates (due to low protein binding). |
| Bioavailability | Oral: <35% due to extensive first-pass hepatic metabolism (dealkylation). Intramuscular: ~100% bioavailability (but slower absorption; peak at 10–15 min). Topical: Variable (5–20% depending on site and integrity of skin/mucosa). Epidural: Dosed to produce local effect; systemic absorption occurs with similar bioavailability to IM. |
| Onset of Action | Intravenous: 30–90 seconds (antiarrhythmic effect). Epidural: 5–15 minutes. Subcutaneous infiltration: <1 minute. Topical (e.g., on mucous membranes): 2–5 minutes. |
| Duration of Action | Intravenous: 10–20 minutes (antiarrhythmic effect). Epidural: 60–90 minutes. Subcutaneous: 30–120 minutes (depending on vasoconstrictor addition). Topical: 15–30 minutes. |
| Molecular Weight | 270.8 |
Intravenous administration: 1-1.5 mg/kg bolus, followed by 1-4 mg/min continuous infusion for ventricular arrhythmias. Maximum total dose: 3 mg/kg bolus; infusion for up to 24 hours. Note: 0.4% concentration = 4 mg/mL, 5% dextrose as diluent.
| Dosage form | INJECTABLE |
| Renal impairment | No specific dose adjustment required for GFR; lidocaine is extensively hepatically metabolized. However, accumulation of metabolites may occur in severe renal impairment (GFR < 10 mL/min) but clinical significance is unclear. Caution advised. |
| Liver impairment | Child-Pugh Class A: Reduce infusion rate by 50%. Child-Pugh Class B: Reduce infusion rate by 75%. Child-Pugh Class C: Contraindicated or use only with extreme caution; reduce dose by 75-90% and monitor closely. Avoid loading doses in severe hepatic impairment. |
| Pediatric use | Loading dose: 1 mg/kg IV bolus, may repeat once after 5-10 minutes if needed (total max 2 mg/kg). Continuous infusion: 20-50 mcg/kg/min (0.02-0.05 mg/kg/min). Adjust based on response and toxicity. Use preservative-free formulations. |
| Geriatric use | Initiate at lower end of dosing range: reduce infusion rate by 50% due to decreased hepatic clearance and increased risk of toxicity. Monitor for CNS and cardiac adverse effects closely. |
| 1st trimester | Lidocaine crosses the placenta. Use only if clearly needed; fetal bradycardia reported. Avoid paracervical block in obstetrics due to risk of fetal bradycardia. |
| 2nd trimester | Use with caution; no teratogenic effects documented in human studies, but fetal bradycardia possible. Administer lowest effective dose. |
| 3rd trimester | Use with caution near term; may cause fetal bradycardia, especially with paracervical block. Avoid high doses; oxytocic effect possible. |
Clinical note
Beta-blockers may increase the risk of lidocaine toxicity Can cause CNS toxicity (seizures) and cardiovascular collapse.
| FDA category | Animal |
| Placental transfer | Lidocaine readily crosses the placenta via passive diffusion. Fetal/maternal plasma concentration ratio is approximately 0.5–0.7. |
■ FDA Black Box Warning
Not for IV or intra-arterial administration due to risk of systemic toxicity and neurological injury. Solutions containing dextrose are contraindicated in patients with known allergy to corn or corn products.
| Common Effects | ventricular arrhythmias |
| Serious Effects |
Hypersensitivity to lidocaine or any amide-type local anestheticSevere hypotension or cardiogenic shockThird-degree atrioventricular block (without pacemaker) when used intravenouslySevere hepatic impairment (due to reduced metabolism)
| Precautions | Use with extreme caution in patients with severe hepatic disease, heart block, or hypovolemia., Monitor for signs of CNS toxicity (dizziness, confusion, seizures) and cardiovascular depression (bradycardia, hypotension)., Avoid extravasation (dextrose solutions can cause tissue necrosis). |
| Food/Dietary |
Loading safety data…
| Breastfeeding |
| Lidocaine is excreted into breast milk in small amounts (milk:plasma ratio ~0.4). At maternal doses, it is generally considered compatible with breastfeeding. Monitor infant for drowsiness or irritability; unlikely to cause adverse effects due to low oral bioavailability. |
| Lactation Rating | L2 (Safer) |
| Teratogenic Risk | Lidocaine hydrochloride is classified as FDA Pregnancy Category B. No teratogenic effects have been observed in animal studies, but there are no adequate and well-controlled studies in pregnant women. Use only if clearly needed. In the first trimester, risk is low but not zero; second and third trimesters: fetal bradycardia may occur with high maternal serum levels or inadvertent intravascular injection. |
| Fetal Monitoring | Monitor maternal vital signs, ECG, and neurological status during administration. Fetal heart rate monitoring is recommended if administered during labor. After epidural or spinal use, assess maternal motor block, blood pressure, and signs of systemic toxicity (e.g., dizziness, perioral numbness, metallic taste). |
| Fertility Effects | No adverse effects on fertility have been reported in animal studies. Lidocaine is not known to impair human reproductive function at therapeutic doses. |
| No clinically significant food interactions. |
| Clinical Pearls | Lidocaine 0.4% with dextrose 5% is typically used for continuous epidural or intrapleural infusion for pain management. The dextrose provides tonicity to prevent hypotonicity but does not add significant calories. Monitor for local anesthetic systemic toxicity (LAST), especially with large doses or rapid infusion. Epinephrine is not present; vascular absorption may be higher. Assess for motor block and sensory level frequently. In epidural use, test dose with epinephrine is not possible; use aspiration and fractionated dosing. |
| Patient Advice | Report any numbness or weakness in arms or legs. · Inform your healthcare provider if you have difficulty breathing, a metallic taste in your mouth, ringing in ears, or lightheadedness. · Do not drive or operate machinery until you know how this medication affects you. · Avoid abrupt movements as you may not feel pain normally. · Keep the infusion site clean and dry; report any redness or swelling. |