Cos de Baha Acid

The Cos De BAHA Hyaluronic Acid 1% Solution Serum is available in 30ml, 60ml, and 240ml formats, all at the same 1% concentration. Hyaluronic acid draws water into the skin from the environment and from deeper skin layers, helping to maintain surface hydration without adding oil. The 240ml size is particularly practical for daily use where a few drops are applied to damp skin before moisturizer.

At 1%, this is a standard working concentration. It is compatible with other actives and can be layered under or over acids since it does not itself exfoliate. It suits all skin types, including sensitive skin, and can be used morning and evening.

The LS Lactic Acid 12.5% Serum Peeling is an alpha hydroxy acid (AHA) exfoliant that dissolves the bonds between dead skin cells at the surface. At 12.5%, it is effective for smoothing texture and addressing mild hyperpigmentation without requiring the stronger concentrations used in clinical peels. Lactic acid also carries a slight humectant property, making it slightly less drying than glycolic acid at equivalent percentages.

Use at night on dry skin after cleansing. Avoid layering with other strong AHAs, retinoids, or vitamin C in the same application. SPF the following morning is necessary because AHAs increase photosensitivity.

The Glycolic Acid AHA 10% Serum targets the same surface exfoliation as lactic acid but with a smaller molecule that penetrates slightly faster. At 10%, it is in the effective range for evening skin tone and improving fine surface lines. The 30ml bottle is well suited to patch-testing or rotating alongside other actives rather than daily use.

Glycolic acid works at a lower pH and is more photosensitizing than lactic acid, so nighttime use and consistent morning SPF application are both necessary. Those new to AHAs should start with lactic acid before introducing glycolic.

The AZ15 Azelaic Acid 15% Serum targets acne-prone skin and post-inflammatory pigmentation (PIH) through a different mechanism than AHAs. Azelaic acid inhibits an enzyme involved in melanin overproduction and also has antibacterial properties relevant to acne. At 15%, it is at the prescription-level threshold, making it one of the stronger over-the-counter options available.

Unlike AHAs, azelaic acid is stable in daylight and does not require strict nighttime application, though SPF remains a good practice. It is particularly effective for people dealing with both active blemishes and the dark marks they leave behind.

Cos De BAHA offers tranexamic acid in three distinct formulas. The T3 Toner uses 3% tranexamic acid in a 200ml toner format for daily brightening. The TN Serum combines 5% tranexamic acid with 5% niacinamide for a two-active whitening approach. The T15 Glutathione Serum uses 15% tranexamic acid alongside glutathione for a more concentrated brightening treatment.

Tranexamic acid works by blocking tyrosinase pathways that trigger melanin overproduction, making it effective against melasma and sun-induced discoloration. It is generally better tolerated than many brightening actives and does not cause the photosensitivity that AHAs do, so it can be used morning or evening.

Cos De BAHA labels most products with a short alphanumeric code that encodes the key active. LS references lactic acid, AZ references azelaic acid, T or TN references tranexamic acid, and the number following typically references the concentration percentage. This system is consistent across the line and makes it easy to compare options when building a routine without reading through full ingredient lists each time.

The coding system also means it is straightforward to cross-reference Cos De BAHA products with existing routines or ingredient research - the label tells you what is in the bottle at a glance.

Using more than one acid product from the Cos De BAHA range at once requires attention to order and compatibility. Hyaluronic acid can be used independently of timing and layered freely. AHAs (lactic, glycolic) and tranexamic acid should not be applied in the same step; pick one exfoliant per session and alternate evenings if using both. Azelaic acid pairs well with niacinamide (already combined in the TN serum) but should not be layered directly over a fresh AHA application.

A conservative approach is one exfoliating acid three to four nights per week, hyaluronic acid daily, and a tranexamic or azelaic treatment on the nights without AHA use. This avoids barrier disruption from over-exfoliation while still addressing multiple concerns.

For first-time acid users, the Hyaluronic Acid 1% Serum is risk-free and a logical starting point - it hydrates without exfoliating and helps you understand how serums fit into a routine. The next step is typically lactic acid at 12.5%, which is gentler than glycolic acid and less irritating than high-percentage AHAs. Patch-test on the inner arm for 24 hours before applying to the face.

From there, adding tranexamic acid in the T3 toner format is a low-risk way to introduce brightening support, since tranexamic acid is well tolerated. Azelaic and glycolic acids are better introduced once the skin has adjusted to regular exfoliation.