Isntree Hyper Acid4 AHA BHA PHA LHA 30 Serum 20ml

High-intensity exfoliation in just 1 minute with a wash-off formula

A rinse-off peeling serum formulated with a total of 30% acid complex featuring four types of exfoliating acids: AHA, BHA, PHA, and LHA. It gently dissolves dead skin cells and pore-clogging sebum, making it a comfortable alternative for those who find physical scrubs too harsh. The black formula is enriched with charcoal powder and peat water. After cleansing, apply to the face, massage gently for 1 minute, then rinse thoroughly with lukewarm water.

Visible skin improvements after a single use

In a human application test conducted on 22 participants, a single use showed the following improvements:

• Sebum in pores improved by 152.72%
• Blackheads improved by 119.45%
• Whiteheads improved by 139.81%
• Skin texture improved by 104.21%

User satisfaction surveys also recorded positive responses of 100% for skin texture improvement, 100% for clearer-looking pores, and 95% for improvements in sebum, blackheads, and whiteheads.

A balanced blend of four acid types

15.3% AHA (exfoliating agents) composed of glycolic acid, lactic acid, and citric acid refines surface texture, while 0.1% salicylic acid-based BHA (pore-clearing agent) targets sebum deep within pores. 14.61% gluconolactone-based PHA (gentle exfoliating agent) delivers exfoliation and hydration simultaneously, and 0.01% capryloyl salicylic acid-based LHA (sebum-regulating agent) enhances the peeling effect while minimizing irritation. Niacinamide (tone-evening) and allantoin (soothing) are also included to care for skin post-peel. Recommended for those concerned with excess sebum, makeup lifting due to dead skin buildup, and shine. Due to the high acid concentration, use 1–2 times per week.

After cleansing, as a rinse-off exfoliating step

Unlike typical serums, this is a wash-off formula designed to be used right after cleansing on towel-dried skin. Apply it as the very first step in your routine, before toner or essence, to gently remove dead skin cells and excess sebum. Massage for 1 minute, rinse thoroughly, then continue with your usual skincare.

Best used in the evening

This is a high-strength exfoliating treatment with a total of 30% acids: AHA (exfoliates surface dead skin), BHA (dissolves pore-clogging debris), PHA (gentle exfoliation for sensitive skin), and LHA (helps control sebum). We recommend using it at night when there's no sun exposure. If you do use it during the day, always follow with a broad-spectrum sunscreen.

Dispense with dropper, massage for 1 minute, then rinse

Using the dropper, apply an appropriate amount to your entire face, avoiding the eye and lip areas. Gently spread the serum along your skin's texture, then massage in light, rolling motions for 1 minute. Rinse thoroughly with lukewarm water, making sure no residue is left behind.

Pairing suggestions by skin concern

• For excess sebum and blackheads: Follow with a lightweight toner and a fresh, hydrating moisturizer
• For flaky texture that disrupts makeup: Layer a soothing essence after exfoliating to smooth and refine skin
• For very oily, shiny skin: Finish with an oil-free hydrating gel cream for a lightweight feel

High-acid formula — please note

Use 1–2 times per week, adjusting frequency based on your skin's condition. A slight tingling sensation is normal, but if it becomes painful, rinse immediately and discontinue use. Do not leave on for longer than 1 minute to avoid irritation, and avoid using retinol or other exfoliating treatments on the same day.

Water, Gluconolactone, Lactic Acid, Methylpropanediol, Glycolic Acid, Potassium Hydroxide, 1,2-Hexanediol, Diethoxyethyl Succinate, Glycerin, Xanthan Gum, Polyglyceryl-10 Laurate, Acacia Senegal Gum, Polyglyceryl-10 Myristate, Glyceryl Caprylate, Niacinamide, Salicylic Acid, Allantoin, Disodium EDTA, Ethylhexylglycerin, Peat Water, Citric Acid, Hydroxypropyl Methylcellulose, Capryloyl Salicylic Acid, Butylene Glycol, Potassium Sorbate, Charcoal Powder

The list of ingredients is subject to change. Please consult the packaging of the product purchased.