The Niacinamide 15 Serum - COSRX

Start with once a day, preferably in the morning or evening. You can increase the frequency to twice a day if your skin tolerates it well.

It is not recommended to use with Vitamin C or AHAs/BHAs at the same time to avoid potential irritation. Alternate the application times, for example, niacinamide in the morning and other actives in the evening.

Purging is a common reaction. Continue using the serum and the purging should subside within a few weeks. If the condition worsens or persists, stop using and contact a dermatologist.

Yes, it is designed to be hypoallergenic and fragrance-free. However, a patch test is recommended before full application to check for any adverse reactions.

Results can vary. Many users see improvements within 4-8 weeks of consistent use. Individual results depend on skin type and condition.

Store the serum in a cool, dark place away from direct sunlight.

Refer to the packaging for the specific period-after-opening (PAO) symbol, which indicates how long the product is good for after opening.

Reduce the frequency of application or use a smaller amount. Perform a patch test before the next application. If irritation persists, discontinue use and consult a dermatologist.

This is a normal reaction as the skin adjusts. Continue using the serum and the purging should subside within a few weeks. If breakouts worsen or persist, consult a dermatologist.

Be patient and continue consistent use for at least 4-8 weeks. Results may vary depending on skin type and severity of the condition. Ensure you are using other compatible products. If you still see no changes, consult a dermatologist.