When is the use of lidocaine 5% patches contraindicated (e.g., hypersensitivity, broken or inflamed skin, children, severe hepatic impairment, high‑grade atrioventricular block or severe bradyarrhythmias, use of class I anti‑arrhythmic agents, or concurrent lidocaine‑containing products)?

Contraindications for Lidocaine 5% Patches

Lidocaine patches are absolutely contraindicated in patients with advanced liver failure, known hypersensitivity to amide-type local anesthetics, and when applied to broken or inflamed skin. 1, 2, 3

Absolute Contraindications

Advanced Hepatic Dysfunction

• Severe liver failure dramatically reduces lidocaine clearance by 60%, creating risk of systemic toxicity even with topical application despite minimal absorption under normal circumstances. 3
• Hepatic impairment increases the elimination half-life and makes plasma drug levels unpredictable, raising the risk of myocardial depression, drowsiness, disorientation, muscle twitching, and seizures. 1, 3

Known Hypersensitivity to Amide Anesthetics

• Hypersensitivity to lidocaine or other amide-type local anesthetics is an absolute contraindication due to risk of delayed-type hypersensitivity reactions. 1, 2, 3
• Contact allergy to lidocaine can present as treatment failure, typical contact dermatitis, or local skin reactions, with delayed hypersensitivity occurring more frequently than previously recognized. 4, 5
• Cross-reactivity may occur with other amide anesthetics such as mepivacaine, though bupivacaine often tests negative in lidocaine-allergic patients. 4

Application to Compromised Skin

• Never apply patches to broken, inflamed, or non-intact skin, as this dramatically increases systemic absorption and toxicity risk. 2, 3
• Manufacturers explicitly warn against application to open wounds. 3

Relative Contraindications and Special Precautions

Significant Cardiac Disease

• Exercise caution in patients with severe cardiac disease, as systemic absorption can theoretically cause cardiac arrhythmias, bradycardia, and myocardial depression, though this is uncommon with proper topical use. 3
• Important distinction: Cardiovascular monitoring requirements and toxicity warnings from IV lidocaine guidelines do not apply to patches due to minimal systemic absorption (plasma levels remain well below the 5 μg/mL threshold associated with toxicity). 6, 3

Pediatric Use

• Lidocaine patches should not be used in patients weighing <40 kg, based on safety data from systemic lidocaine studies. 6

Critical Timing Restrictions

Concurrent Local Anesthetic Use

• Do not use lidocaine patches within 4 hours of any other local anesthetic intervention (nerve blocks, fascial plane blocks, epidural boluses, or infiltration) to prevent cumulative toxicity. 6, 2, 3
• Remove all topical lidocaine patches before starting intravenous lidocaine infusion. 6
• Wait 4 hours after completing IV lidocaine before performing any nerve blocks or giving local anesthetic boluses. 6

Application Parameters to Prevent Toxicity

Maximum Duration and Dosing

• Never exceed 12 hours of continuous application, even if pain persists, as elimination half-life increases dramatically from 100 minutes to 3.22 hours beyond 12 hours, making drug levels unpredictable. 1
• Mandatory 12-hour patch-free interval must follow each 12-hour application period to minimize systemic toxicity and skin sensitization risk. 1, 2
• Maximum of 3-4 patches may be applied simultaneously, but the 12-hour duration limit still applies regardless of number used. 1, 3

Heat Exposure

• Avoid excessive heat application over patch areas (heating pads, hot water bottles, electric blankets), as heat increases systemic absorption and could lead to toxicity. 1, 2

Monitoring for Systemic Toxicity

Watch for signs of systemic absorption, though uncommon with proper use: 1, 3

• Dizziness and confusion
• Drowsiness or altered consciousness
• Bradycardia
• Muscle twitching
• Perioral numbness or tingling tongue/lips
• Perform periodic skin checks for irritation or sensitization at application sites. 1

Common Clinical Pitfalls

• Do not assume pacemakers are a contraindication for topical lidocaine patches—this restriction applies only to intravenous lidocaine, not patches. 3
• Elderly patients (>70 years) are at higher risk with systemic lidocaine but remain safe candidates for patches due to minimal absorption. 3
• No dose adjustment required for renal impairment, unlike gabapentin or pregabalin. 2, 3
• Patches are most effective for well-localized, superficial neuropathic pain rather than deep radicular pain or widespread pain distribution. 1, 2