Ships from California or direct from Korea, tracked to your door

Free US shipping on orders of $100 or more. 100% authentic Korean-market formulas. Ships from California or direct from Korea, tracked to your door. Intact Korean batch codes on every unit.

Shipping details
KOREAN PHARMACY

Isntree

Share
Copy linkhttps://korean-pharmacy.com/products/isntree-hyper-acid-4-aha-bha-pha-lah-30-serum-20ml

Hyper Acid 4 (AHA BHA PHA LAH) 30 Serum 20ml

Isntree Hyper Acid 4 (AHA BHA PHA LAH) 30 Serum is a 20ml serum with Salicylic Acid, used after toner and before moisturizer, morning and evening.

No reviews yet
$15.00

20 ml

$7.50 per 10 ml

  • Korean-market formula
  • Ships from California or direct from Korea
  • Korean barcode and batch code intact
Suited to
OilyCombinationBlemish-proneNormal
Helps with
Rough texture on sensitised skinDull, rough surface textureDullness and an uneven-looking toneClogged pores and recurring breakouts

Purchase options

In stock. Arrives in 3 to 7 business days

We accept

You’re $100.00 away from free US shipping.

  • 30-day returns
  • Free US shipping on orders of $100 or more
  • Tracked delivery to your door

How it works

The Hyper Acid 4 (AHA BHA PHA LAH) 30 Serum is a 20ml serum, used after toner and before moisturizer, morning and evening. 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 serum format rather than by the list alone. This is the Original Korean Formula, the serum Isntree sells in Korea, Salicylic Acid and all.

Key benefits

  • Salicylic Acid, the exfoliant this serum 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
  • The Korean-market release of this serum, confirmed against its Korean barcode

Inside the formula

Inside the formula

26
Ingredients declared
No fragrance
on the list

1 of 5

Isntree Hyper Acid 4 (AHA BHA PHA LAH) 30 Serum 20ml

How to use

  1. Start at two nights a week and only increase if the skin stays completely comfortable.
  2. Apply a thin layer to clean dry skin, concentrating on the rougher areas rather than the whole face.
  3. Follow with a plain moisturiser afterwards so the surface is not left bare.
  4. Do not use it on the same night as a retinoid or another acid, since stacking is what turns a routine sore.

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.

Complete the routine

Total for 3 items$75.00

Reviews

No reviews yet. Tell us how much you love the product!

Write a review

Isntree Hyper Acid 4 (AHA BHA PHA LAH) 30 Serum 20ml

How it felt, how your skin took it, what you layer it with. Straight answers help the next person choose.

Your rating

Your email is never shown on the store.

Read every customer review

We’re on gram!

Creators trying on authentic Korean skincare routines and products from us.

  • Rating a shelf of Dr. Althea products one by one.

    Jasmine Loo · YouTube

  • Two hydrating serums side by side, IUNIK and Dr. Althea.

    Kristin · YouTube

  • A walk through the Dr. Althea serum lineup and who each one suits.

    auraofmahmuda · YouTube

  • A blunt first take on the Dr. Althea range.

    Lexi Chang · YouTube

  • A first look at the viral 345 Relief Cream before buying.

    Shelley Nayak · YouTube

  • A first try of the Dr. Althea serum on camera.

    Hannah Ziad · YouTube

Isntree, Korean-market original

The Original Korean Formula serum from Isntree, 20ml formulated with Salicylic Acid and Niacinamide, shipped from California or direct from Korea.

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.

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 skin care, quoted from the medical sources linked beside each.

  • Your skin barrier is basically your outer layer of the skin.

    Melissa Piliang, MDDermatologist, Cleveland Clinic
  • Pretty much every step of a Korean skin care routine is going to have some component of hydration.

    Alok Vij, MDDermatologist, Cleveland Clinic

Ask an AI assistant about this product

Ask an AI assistant about this product

Opens ChatGPT, Perplexity or Claude in a new tab with the question prefilled. Claude asks you to sign in first.