GLYDO
Clinical safety rating: caution
Comprehensive clinical and safety monograph for GLYDO (GLYDO).
GLYDO (lidocaine) is an amide-type local anesthetic that stabilizes the neuronal membrane by inhibiting sodium ion channels, thereby blocking the initiation and conduction of nerve impulses.
| Metabolism | Primarily hepatic via CYP1A2, with minor contributions from CYP3A4; metabolites include monoethylglycinexylidide (MEGX) and glycinexylidide (GX). |
| Excretion | Renal excretion of unchanged drug accounts for approximately 10% of the dose; the remainder is metabolized in the liver to inactive metabolites that are excreted renally. Fecal elimination is negligible (<2%). |
| Half-life | Terminal elimination half-life is approximately 1.5 to 2 hours in adults with normal hepatic and renal function. In neonates, half-life is prolonged (up to 3-4 hours) due to immature hepatic metabolism. |
| Protein binding | 60-80% bound to alpha-1-acid glycoprotein (AAG); binding is concentration-dependent and decreases with high drug levels. |
| Volume of Distribution | Volume of distribution is approximately 1.1 L/kg (range 0.6-1.5 L/kg). Higher Vd in heart failure (up to 2.5 L/kg) due to increased perfusion of adipose tissue. |
| Bioavailability | Intravenous: 100%; Intramuscular: 80-90% (due to first-pass metabolism); Oral: approximately 35% (extensive first-pass metabolism, only used for prophylaxis). |
| Onset of Action | Intravenous: 1-2 minutes; Intramuscular: 5-10 minutes; Oral (as antiarrhythmic): 30-60 minutes. |
| Duration of Action | Intravenous: 10-20 minutes (single bolus) due to rapid redistribution; continuous infusion required for sustained effect. Intramuscular: 30-60 minutes. Oral: 2-4 hours. |
| Molecular Weight | 234.34 |
For anesthesia: 1-5% solution, 0.5-5 mg/kg IV or 2.5-15 mg intrathecally; for antiarrhythmic: 1-1.5 mg/kg IV bolus then 1-4 mg/min infusion.
| Dosage form | JELLY |
| Renal impairment | No specific dose adjustment required; use with caution in severe renal impairment (GFR <30 mL/min) due to accumulation of metabolites. |
| Liver impairment | Child-Pugh A: no adjustment; Child-Pugh B: reduce dose by 50%; Child-Pugh C: reduce dose by 75% or avoid use. |
| Pediatric use | Antiarrhythmic: loading dose 1 mg/kg IV, maintenance 20-50 mcg/kg/min; local anesthesia: max 4.5 mg/kg (7 mg/kg with epinephrine). |
| Geriatric use | Reduce initial dose by 50%; monitor for toxicity; clearance may be decreased due to reduced hepatic blood flow. |
| 1st trimester | Avoid due to potential teratogenicity. Note: GLYDO (lidocaine) is generally considered low risk, but high doses may be associated with fetal bradycardia. Use only if clearly needed. |
| 2nd trimester | Use with caution. Monitor fetal heart rate. Lidocaine crosses placenta; may cause fetal CNS depression. |
| 3rd trimester | Use with caution near term; may cause neonatal CNS depression and bradycardia. Avoid high doses or repeated administration. |
Clinical note
Comprehensive clinical and safety monograph for GLYDO (GLYDO).
| Placental transfer | Lidocaine crosses the placenta rapidly by passive diffusion. Fetal/maternal ratio approximately 0.5-0.7. Higher transfer in acidosis. |
| Breastfeeding | Lidocaine is excreted into breast milk in small amounts; considered compatible with breastfeeding. However, monitor infant for signs of toxicity (e.g., drowsiness, poor feeding) with prolonged use. |
■ FDA Black Box Warning
Not applicable; no FDA black box warning for lidocaine.
| Serious Effects |
Hypersensitivity to lidocaine or amide-type anestheticsSevere heart block (without pacemaker)Stokes-Adams syndromeWolff-Parkinson-White syndrome (when used intravenously)
| Precautions | Cardiotoxicity: can cause arrhythmias, hypotension, or cardiac arrest at high doses, CNS toxicity: seizures, respiratory depression, especially with rapid absorption or overdose, Anaphylactic reactions: rare but severe allergic reactions may occur, Methemoglobinemia: associated with certain formulations (e.g., benzocaine-containing products), Hepatic impairment: decreased metabolism, increased risk of toxicity |
| Food/Dietary | No specific food interactions known; however, avoid alcohol as it may increase dizziness or sedation. |
Loading safety data…
| Lactation Rating | L2 (Possibly Safe) |
| Teratogenic Risk | GLYDO (lidocaine HCl) is classified as FDA Pregnancy Category B. Animal studies have not demonstrated teratogenic effects; however, there are no adequate and well-controlled studies in pregnant women. Lidocaine crosses the placenta. In the first trimester, risk cannot be excluded. During the second and third trimesters, use only if clearly needed. At term, lidocaine may cause fetal bradycardia, neonatal respiratory depression, or CNS effects due to potential for accumulation. |
| Fetal Monitoring | Monitor maternal heart rate, blood pressure, and level of consciousness for signs of systemic toxicity. Assess fetal heart rate pattern (continuous electronic fetal monitoring) during labor and delivery to detect fetal bradycardia or non-reassuring changes. Monitor for neonatal adverse effects such as respiratory depression, hypotonia, or seizures post-delivery if lidocaine was used near term. |
| Fertility Effects | Lidocaine has no known direct effects on fertility based on animal studies. No human data are available. Local anesthetics do not typically impact reproductive function at clinical doses. However, high systemic concentrations could theoretically interfere with sperm motility or uterine contractility, but this is not clinically relevant with standard dosing. |
| Clinical Pearls | GLYDO (combination of glycopyrrolate and lidocaine) is used for topical anesthesia with anticholinergic effects. Avoid use in patients with narrow-angle glaucoma, myasthenia gravis, or tachyarrhythmias. Monitor for anticholinergic side effects (dry mouth, blurred vision, urinary retention). Use with caution in hepatic or renal impairment. |
| Patient Advice | Avoid driving or operating machinery immediately after application due to potential blurred vision or dizziness. · Do not apply to broken or irritated skin. · Inform your doctor if you have glaucoma, heart problems, or difficulty urinating. · Side effects may include dry mouth, dry eyes, or temporary numbness. |