LIDOCAINE HYDROCHLORIDE 0.8% IN 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 an amide-type local anesthetic that acts by blocking voltage-gated sodium channels in neuronal cell membranes, thereby inhibiting the initiation and conduction of nerve impulses. This stabilizes the neuronal membrane and produces a reversible loss of sensation.
| Metabolism | Primarily metabolized in the liver via oxidative N-dealkylation by CYP1A2 and CYP3A4 to monoethylglycinexylidide (MEGX) and further to glycinexylidide (GX). |
| Excretion | Lidocaine is primarily metabolized in the liver by CYP1A2 and CYP3A4 to active metabolites (MEGX, GX). Less than 10% is excreted unchanged in urine. Renal excretion accounts for about 20% of total clearance as metabolites and parent drug; fecal elimination is minimal (<5%). |
| Half-life | Terminal elimination half-life is approximately 1.5–2.0 hours after a single IV dose. In patients with heart failure or hepatic impairment, it may be prolonged to >3 hours. After continuous infusion, the half-life may increase due to accumulation. |
| Protein binding | 60–80% bound primarily to albumin and alpha1-acid glycoprotein (AAG). Binding is saturable and decreases in conditions with low AAG (e.g., neonates) or high lidocaine concentrations. |
| Volume of Distribution | Vd = 1.1–2.1 L/kg. Volume increases in heart failure (due to reduced cardiac output) and decreases in hemorrhagic shock. |
| Bioavailability | Oral bioavailability is very low (≈35%) due to extensive first-pass metabolism. For IV administration, bioavailability is 100%. For epidural or local infiltration, bioavailability is essentially 100% as the drug is not subject to first-pass elimination at the site. |
| Onset of Action | IV administration: 45–90 seconds. For epidural or peripheral nerve block: 5–15 minutes. For topical application: 2–5 minutes. |
| Duration of Action | IV bolus (antiarrhythmic): 10–20 minutes. Infusion: during infusion and short-lived after discontinuation. Epidural: 60–90 minutes (with epinephrine). Local infiltration: 30–120 minutes (dose-dependent). |
| Molecular Weight | 270.8 |
Intravenous administration: 1-1.5 mg/kg bolus, followed by 1-4 mg/min continuous infusion for ventricular arrhythmias. Max dose: 3 mg/kg bolus, 4 mg/min infusion.
| Dosage form | INJECTABLE |
| Renal impairment | No dose adjustment required for mild-moderate renal impairment. In severe renal impairment (CrCl <10 mL/min), reduce infusion rate by 25-50% due to accumulation of metabolites. |
| Liver impairment | Child-Pugh Class A: Reduce loading dose by 50% and infusion rate by 50%. Child-Pugh Class B or C: Contraindicated or use with extreme caution; reduce infusion rate by 75% and monitor closely. |
| Pediatric use | Intravenous: Loading dose 1 mg/kg, may repeat once after 5-10 min. Continuous infusion: 20-50 mcg/kg/min. Max: 100 mcg/kg/min. |
| Geriatric use | Reduce loading dose and infusion rate by 50% due to decreased hepatic clearance and increased risk of toxicity. Monitor for CNS and cardiac effects. |
| 1st trimester | Lidocaine crosses the placenta. No increased risk of major malformations has been reported with lidocaine use during first trimester in human studies. However, consider benefit vs risk. |
| 2nd trimester | Lidocaine is safe for use during second trimester for indicated procedures. Fetal bradycardia may occur if large doses are administered paracervically. |
| 3rd trimester | Lidocaine may cause fetal bradycardia and CNS depression if high maternal serum levels are reached. Use lowest effective dose. Not contraindicated for epidural anesthesia when used judiciously. |
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 crosses the placenta by passive diffusion. Fetal plasma levels are approximately 50-60% of maternal levels. Protein binding is lower in fetus, leading to higher free fraction. Extensive placental transfer occurs. |
■ FDA Black Box Warning
NOT FOR SPINAL ANESTHESIA due to risk of hypotension and cardiac arrest when used for spinal anesthesia.
| Common Effects | ventricular arrhythmias |
| Serious Effects |
Hypersensitivity to lidocaine or any amide-type local anestheticsComplete heart block or severe conduction disturbances without pacemakerAdams-Stokes syndromeWolff-Parkinson-White syndrome (for intravenous use as antiarrhythmic)Severe hypotension or cardiogenic shockPorphyria (may precipitate attacks)
| Precautions | Risk of systemic toxicity with inadvertent intravascular injection, Use caution in patients with heart block, hepatic impairment, or severe hypotension, Epidural or caudal anesthesia may cause hypotension, bradycardia, or respiratory arrest, Potential for methemoglobinemia (rare), Monitor for signs of CNS toxicity (dizziness, confusion, seizures) and cardiac toxicity (arrhythmias, cardiac arrest) |
| Food/Dietary |
Loading safety data…
| Breastfeeding | Lidocaine is excreted into breast milk in low concentrations (milk:plasma ratio ~0.4). The estimated daily dose to a nursing infant is less than 1% of the maternal dose, which is unlikely to cause adverse effects. Use with caution in breastfeeding mothers, especially with high doses or prolonged infusion. |
| Lactation Rating | L2 (Probably Compatible) |
| Teratogenic Risk | Lidocaine crosses the placenta. In first trimester, no major malformations reported in human studies, but risk of fetal bradycardia if high maternal levels. In second and third trimesters, placental transfer can cause fetal acidosis and CNS depression. Use only if clearly needed. |
| Fetal Monitoring | Monitor maternal ECG, blood pressure, and respiratory status. Fetal heart rate monitoring during prolonged infusion. Assess for signs of toxicity (perioral numbness, tinnitus, seizures). |
| Fertility Effects | No known impairment of fertility in animal studies. No human data on fertility effects. |
| No specific food interactions. Monitor blood glucose due to dextrose content; adjust insulin or hypoglycemic therapy accordingly. Avoid alcohol as it may increase CNS depression. |
| Clinical Pearls | Premixed lidocaine in D5W is for intravenous administration only; verify concentration (0.8% = 8 mg/mL) to avoid dosing errors. Use in cardiac arrest protocols for ventricular arrhythmias; reduce dose in heart failure or hepatic impairment. Monitor for CNS toxicity (seizures, drowsiness) and cardiac toxicity (bradycardia, hypotension). Avoid in patients with severe bradycardia or heart block. |
| Patient Advice | This medication is given intravenously to treat irregular heartbeats. · It may cause drowsiness, dizziness, or confusion; avoid driving until you know how it affects you. · Report any numbness, tingling, or muscle twitching immediately. · Do not consume alcohol while receiving this medication. · Inform your doctor if you have heart disease, liver problems, or seizures. · This product contains dextrose; if you have diabetes, monitor blood sugar closely. |