Medications · FAQ
What side effects and warning signs can lidocaine cause?
Short answer
Lidocaine can cause local burning, irritation, redness, or unwanted numbness. Too much can cause serious problems involving the brain, heart, or blood oxygen levels. Stop using it and seek urgent help for trouble breathing, blue or gray lips, seizures, fainting, or a fast or irregular heartbeat. Call 911 for severe symptoms.
Side effects can include stinging, burning, redness, or irritation where lidocaine is applied. Mouth products may affect taste or leave nearby tissue numb. Penile products may cause unwanted loss of sensation. Tell your prescriber if these effects are bothersome, persistent, or getting worse.
Using too much lidocaine, applying it too often, or treating a large or damaged area can increase absorption into the blood. Warning signs of toxicity can include ringing in the ears, dizziness, confusion, unusual sleepiness, shaking, or an abnormal heartbeat. Do not take another dose if you suspect a toxic reaction.
Rarely, lidocaine can cause methemoglobinemia, a condition that reduces the blood's ability to carry oxygen. Symptoms can include pale, gray, or blue skin or lips, shortness of breath, headache, and unusual tiredness.
Call 911 for breathing trouble, seizures, collapse, severe confusion, or signs of a serious allergic reaction, such as facial swelling. For a possible overdose without severe symptoms, call Poison Control at 1-800-222-1222 right away rather than waiting.
Sources
Written by the Verra clinical team · Medical review pending
General information, not medical advice. If you're in crisis, call or text 988.