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KOREAN PHARMACY

Isntree

Hyper Acid4 AHA BHA PHA LHA 30 Serum 20ml (Wash-off)

Isntree Hyper Acid4 AHA BHA PHA LHA 30 Serum 20ml (Wash-off) is a 20ml peeling gel with Salicylic Acid, used after cleansing, in place of the toner step, on two evenings a week.

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$18.99
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Suited to
OilyCombinationBlemish-proneNormal
Helps with
Rough texture on sensitised skinDull, rough surface textureDullness and an uneven-looking toneClogged pores and recurring breakouts

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How it works

The Hyper Acid4 AHA BHA PHA LHA 30 Serum 20ml (Wash-off) is a 20ml peeling gel, used after cleansing, in place of the toner step, on two evenings a week. The exfoliant it is built around is Salicylic Acid, named sixteenth on its own ingredient list. The same list carries Niacinamide, Allantoin and Gluconolactone, so the exfoliant is not the only thing on it worth naming. How much of the Salicylic Acid stays on the skin, and for how long, is decided by the peeling gel format rather than by the list alone. Isntree sells this Salicylic Acid peeling gel in Korea, and this is that version.

Key benefits

  • Salicylic Acid, the exfoliant this peeling gel is built around
  • Niacinamide and Allantoin on the same list, actives
  • Gluconolactone and Lactic Acid on the same list, exfoliants
  • Glycolic Acid and Capryloyl Salicylic Acid further down the same list
  • Salicylic Acid named sixteenth on the manufacturer list printed on this page

Key actives

Salicylic Acidexfoliant

It loosens the dead cells that block pores and is used for the look of congested, oily skin. It is the entry this peeling gel is named after, and the list carries it.

Niacinamideactive

Niacinamide is vitamin B3, and it is the most studied active in Korean formulation. The panel names it fifteenth on this peeling gel's list, beside Salicylic Acid.

Allantoinactive

Allantoin is a comfrey-derived compound used to condition skin and soften the outer layer so it feels smoother. It is one of the standard additions to a formula built for easily irritated skin. It is named seventeenth on this peeling gel's list, alongside Salicylic Acid.

Gluconolactoneexfoliant

Gluconolactone is a PHA, the gentlest exfoliant class. The panel names it second on this peeling gel's list, beside Salicylic Acid.

Lactic Acidexfoliant

Lactic Acid is a larger AHA than glycolic, so it works nearer the surface and is easier on skin, and it is a humectant as well as an exfoliant. It is the AHA of choice for dry skin. It is named third on this peeling gel's list, alongside Salicylic Acid.

Isntree Hyper Acid4 AHA BHA PHA LHA 30 Serum 20ml (Wash-off)

Isntree Hyper Acid4 AHA BHA PHA LHA 30 Serum 20ml (Wash-off)

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How to use

  1. Use the Hyper Acid4 AHA BHA PHA LHA 30 Serum 20ml (Wash-off) after cleansing, in place of the toner step, on two evenings a week.
  2. A thin layer over dry skin, kept clear of the eye area and the corners of the mouth.
  3. Rinse or roll it off as the pack directs, then follow with a hydrating layer and your moisturizer the same evening.
  4. Two evenings a week is the ceiling. Do not pair it with an acid toner or a retinoid in the same routine.

Worth knowing

  • Introduce gradually if skin is new to acid exfoliation, watching for stinging on first use.
  • Introduce gradually alongside other acids to avoid overloading a routine that already exfoliates.
  • Start with a lower frequency if skin is new to BHA exfoliation, since daily use can feel like too much at first.
  • Patch test on the inner arm before a first full-face application if skin tends to react easily.

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Isntree, Korean-market original

The Original Korean Formula peeling gel from Isntree, 20ml formulated with Salicylic Acid and Niacinamide, held in the United States and shipped domestically.

Verify your unit when it arrives

Verify your unit when it arrives

Korean-market stock with the original barcode and batch code intact, exactly as it left Korea.

Match the batch code on the box against the code printed on the bottle or tube itself; the two are stamped separately and should agree.

On the unit itself

  • The Korean-market barcode, unaltered from the retail package.
  • The manufacturer’s batch code, exactly as the maker printed it.

정품Genuine article, Korean-market stock

What professionals say

What professionals say

What skin-care professionals say about the key actives in this formula, quoted from the medical sources linked beside each.

  • BHAs like salicylic acid get really deep into the pores, whereas the water-soluble ones don't go as deep.

    Samantha Stein, PA-CDermatology physician assistant, Cleveland Clinic
  • Allantoin can tone down the dryness of the individual cells. It increases the water content of the skin, which means it helps to hydrate and moisturize.

    Wilma Bergfeld, MDDermatologist, Cleveland Clinic
1 more professional perspective
  • Niacinamide helps reduce the appearance of pores in a few ways. By strengthening the skin barrier and improving elasticity, pores appear less noticeable and more even.

    Ashlyn YankeAesthetician, Cleveland Clinic

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