Viscous Lidocaine Safety and Usage Guidelines

Contraindications and Precautions

The American Society of Anesthesiologists recommends that viscous lidocaine be used with caution in patients with cardiac disease, electrolyte disorders, seizure disorders, renal or hepatic impairment, pregnancy, breastfeeding, or neurological disorders 1
Viscous lidocaine should not be used concurrently with other local anesthetic interventions, and its use should be avoided within 4 hours of any nerve block, fascial plane block, or infiltration 1

Early warning signs of toxicity include tingling of tongue or lips, metallic taste, circumoral numbness, and light-headedness, as recommended by the American Heart Association 1
Progressive toxicity manifests as slurred speech, muscle twitching, loss of consciousness, respiratory arrest, cardiac arrhythmias, and ventricular arrest, according to the American College of Cardiology 1

If signs of toxicity appear, the American Academy of Clinical Toxicology recommends immediately discontinuing lidocaine and providing supportive care, including airway management and lipid emulsion therapy for cardiovascular collapse 2