Cos De BAHA - S4 Salicylic Acid 4% Serum

For best results, start by applying a small amount once daily or every other day, preferably in the evening. Gradually increase to twice daily if your skin tolerates it well. Always listen to your skin and adjust frequency as needed.

It's generally advisable to avoid using multiple strong actives (like retinoids, AHAs/BHAs, or Vitamin C) in the same routine to minimize potential irritation. Introduce this serum slowly and see how your skin reacts. If using other actives, consider alternating application times (e.g., serum in AM, retinoid in PM).

While it contains ingredients to soothe irritation, Salicylic Acid can be potent. It's recommended to perform a patch test first. Start with infrequent application (every 2-3 days) and monitor for any signs of redness or discomfort.

The 'S4' likely refers to the Salicylic Acid concentration or a specific product line identifier from Cos De BAHA. In this case, it signifies the 4% concentration of Salicylic Acid (BHA).

Improvements in acne and redness can often be seen within a few days to weeks of consistent use. Fading of hyperpigmentation and significant texture improvement may take 4-8 weeks or longer.

Yes, Salicylic Acid is oil-soluble and can penetrate pores to dissolve sebum and debris, making it very effective at clearing and preventing blackheads.

Absolutely. Exfoliating acids like Salicylic Acid can increase your skin's sensitivity to the sun. Always apply a broad-spectrum sunscreen with SPF 30 or higher daily, even on cloudy days, to protect your skin.

Reduce frequency of application. Ensure you are using a moisturizer and consider applying the serum only a few times a week initially. Drink plenty of water.

Apply a smaller amount and gently tap it into the skin. Allow sufficient time for absorption before applying other products. Ensure you are not applying too many layers of other products beforehand.

Ensure consistent daily or near-daily application. Verify you are applying the correct amount and allowing it to absorb. Be patient, as results for hyperpigmentation and texture take time.

Discontinue use temporarily and allow the skin to recover. When resuming, use less product, apply less frequently, and always patch test. Consider consulting a dermatologist if irritation persists.