What do the Clean, Low, Watch and Swap levels mean?

They are cut from a continuous concern level the app computes from the sourced claims that the chosen evidence lens shows: each claim counts its concern class, tier weight, confidence and dose relevance, combined worst-first with a decay so one serious finding outweighs many small ones, then scaled by how much of the substance reaches you in this use. Clean is below 0.35, Low below 1.1, Watch below 2.0 and Swap above that, on a 0 to 3 scale.

Is Lidocaine safe on skin (left on)?

Q: Is lidocaine safe on skin (left on)?

Under the app's default Cautious lens, lidocaine on skin (left on) rates Watch: worth watching; the app would list a cleaner alternative type. 3 sourced concerns count (restricted, consensus tier; metabolic, consensus tier; irritant · allergen, consensus tier). This is research with sources, not medical advice.

Medicines & supplements1 use researched3 sourced claims

Where it turns up: common topical anesthetic for pain. Detox My Life researched lidocaine under one use, because the same substance means something different in each use. Every claim below carries its evidence tier, how sure the research is that it applies here, and the sources it cites. The level is computed by the app's own deterministic engine, so the page says exactly what the app would.

Level by use and lens

Use	Mainstream	Cautious (default)	Based	Concerns · favour · fringe
On skin, left on	Watch	Watch	Watch	3 · 0

Mainstream shows consensus claims only; Cautious adds emerging research; Based adds fringe claims, labelled as such. The last column counts, under Cautious, the sourced concerns, the findings in its favour and the fringe claims Based would add.

Safer swaps: the app's swap catalog has no entry tied to this ingredient yet. When you scan a product that contains it, the app suggests cleaner alternative types for that product; the swap categories list what the catalog covers today.

On skin, left on Watch

Under the default Cautious lens lidocaine on skin (left on) rates Watch: worth watching; the app would list a cleaner alternative type. Mainstream (consensus only) rates it Watch; Based (adds the fringe) rates it Watch. Researched 2026-09-03.

Sourced concerns (3)

ConsensusRestrictedconfidence 50%

The U.S. Food and Drug Administration (FDA) warns consumers not to use over-the-counter (OTC) topical pain relief products with more than 4% lidocaine on their skin, or to apply them heavily over large areas, to irritated or broken skin, or to wrap treated skin with plastic wrap or other dressings, as these practices can lead to increased absorption and serious adverse effects.

Why here: Dermal leave-on products, especially those with higher concentrations or used improperly (e.g., on large areas, broken skin, or under occlusion), can lead to significant systemic absorption of lidocaine.
What would have to be true: Topical application of lidocaine at concentrations exceeding 4% for OTC products, or application over large body areas, to broken or irritated skin, or under occlusive dressings.

Sources the engine cites:

FDA Warns Consumers to Avoid Certain Topical Pain Relief Products Due to Potential for Dangerous Health Effects — fda.gov (2024) · regulator or public body
3 web articles (healio.com, psychiatrist.com, lachmanconsultants.com), linked in the app.

ConsensusMetabolicconfidence 50%

Topical lidocaine can cause methemoglobinemia, a rare but serious blood disorder where hemoglobin in red blood cells is unable to carry oxygen effectively, potentially leading to life-threatening conditions, especially in children younger than 6 months of age, elderly patients, or individuals with certain inborn defects.

Why here: Systemic absorption of lidocaine from dermal leave-on products can lead to the formation of methemoglobin.
What would have to be true: Dermal application of lidocaine, even at normal use, with increased risk in vulnerable populations or with overuse.

Sources the engine cites:

Systemic Risks of Topical Anesthetics in Barrier-Compromised Dermatologic Patients - PMC — nih.gov (2025) · regulator or public body
Lidocaine (topical application route) - Side effects & dosage - Mayo Clinic — mayoclinic.org (2026) · review
Lidocaine dermal patch - Cleveland Clinic — clevelandclinic.org · review
1 community or commercial page, not counted here.

ConsensusIrritant · allergenconfidence 50%

Topical lidocaine can cause local skin irritation, including redness, itching, burning, rash, and blistering, and in rare cases, serious allergic reactions such as hives, swelling, difficulty breathing, or anaphylaxis.

Why here: Direct contact of lidocaine with the skin during dermal leave-on application can trigger local irritation or allergic responses.
What would have to be true: Dermal application of lidocaine.

Sources the engine cites:

Lidocaine: A Local Anesthetic, Its Adverse Effects and Management - PMC — nih.gov · regulator or public body
Lidocaine (topical application route) - Side effects & dosage - Mayo Clinic — mayoclinic.org (2026) · review
Lidocaine dermal patch - Cleveland Clinic — clevelandclinic.org · review
1 web article (performancepain.com), linked in the app.

Not researched here

The engine has no dossier for lidocaine when cooked with heat, in cold food, as a finishing ingredient, in heated food packaging or other uses. The app researches an ingredient for the use it infers from your product, so a scan fills these in; this page only shows what has already been researched and source-verified.

This is research, not medical advice. Detox My Life shows sourced claims sorted by evidence tier. It does not diagnose, treat, or tell you to start or stop anything. Talk to a qualified professional about your health.

Scan your own. The app reads any product label with your camera, works out how you are about to use it, and researches every ingredient for that use with live sources. Every scan adds to a Detox Score for your home, where 50 is a typical home in your region, and a plan of next swaps.

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