Related

	Strip lash adhesive	Extension adhesive
Base	Latex or acrylate polymer emulsion in water	Cyanoacrylate — the same family as superglue
Sets in	30–60 seconds, by evaporation	1–3 seconds, by polymerising on contact with moisture
Holds for	A day	2–4 weeks
Used by	Anyone	Professionals only
Removed with	Oil, or peeling gently after soaking	A dedicated solvent remover

These are not interchangeable, and the difference matters medically. Professional extension adhesive cures in seconds against the moisture on the skin. Used by an untrained hand, on a moving eye, it can bond the lids together or reach the cornea. The consumer-grade version is deliberately slow so there is time to reposition.

• Cyanoacrylate allergy. The dominant problem in extensions. It is a type IV delayed hypersensitivity, which means it develops with exposure — someone can wear extensions comfortably for years and then react. Swelling, itching and weeping lids, 24–48 hours after a fill.
• Formaldehyde. Cyanoacrylate adhesives can release formaldehyde as they cure and as they degrade. Salon adhesives marketed as "formaldehyde-free" generally mean no formaldehyde was added as an ingredient, which is not the same as none being present — that is a real distinction and worth asking about.
• Latex allergy. Some strip adhesives are latex-based. Anyone with a natural rubber latex allergy needs a latex-free one, and it must be checked rather than assumed.
• Chemical injury to the cornea from adhesive entering the eye. This is an emergency: flush with water and get to an eye clinician; do not rub, and do not try to pull the lids apart.
• Carbon black is used to make the dark adhesives, and its approved uses in cosmetics are use-specific.

1. Patch test on the inner arm 24–48 hours before first use of a new adhesive.
2. Glue on the band, never near the eye.
3. Wait until tacky — around 30 seconds. This is the single most common error; wet glue slides and ends up where it should not.
4. Place above the lash line, not on the waterline.
5. Ventilate. Cyanoacrylate vapour irritates eyes and airways, which is why salons use extraction and why the technician's eyes water too.
6. Remove with oil, soaked and held for twenty seconds. Never pull dry.

Cosmetic in the US — FDA primary category (03) eye makeup preparations. FDA does not approve eyelash adhesives before sale; as with all cosmetics other than colour additives, there is no premarket approval, and the manufacturer carries the responsibility for safety.

What does exist:

• Colour additives in tinted adhesives must be approved for eye-area use.
• Under MoCRA, the small-business exemption from registration and listing does not apply to products that regularly contact the mucous membrane of the eye, and serious adverse events are reportable to FDA within 15 business days — which is the mechanism by which adhesive injuries now become visible to the agency.
• Lash extension application is licensed at state level in most US states through cosmetology boards, with sanitation and training requirements. That is the practical regulation of extension adhesive, and it is not federal.

Short, and shorter than people assume. Cyanoacrylate adhesives degrade once opened — typically 4–8 weeks for a professional adhesive, and salons date their bottles for this reason. Strip adhesives last a few months and thicken as the water evaporates.

Heat and humidity accelerate both. Store upright, cool, tightly closed, and discard any adhesive that has thickened, gone stringy or changed colour — a degraded adhesive both performs worse and releases more.

• Makeup — the shelf this sits on, and the rest of it.
• Cosmetics — what the label is legally allowed to say, and the full catalogue.
• The rest of Eyes — Eyeshadow · Eyeshadow Primer · Eyeliner · Kohl and Kajal · Mascara · Lash Primer · False Eyelashes · Eyelash Serum · Eye Makeup Remover · Eyelash Cleanser.
• Nail Glue — the same cyanoacrylate chemistry, a less delicate target.
• Regulatory statements here follow the FDA and EU sources listed on Cosmetics, read 16 August 2026.