When considering using a skincare product only on areas with open pores and acne instead of the entire face, it's important to understand how the product works and your skin type. Applying the product only to affected areas can be appropriate if the product is targeted for acne treatment or pore care, but if it's a general moisturizer, using it on the whole face helps maintain overall skin hydration.

Applying the product at night and leaving it on overnight is generally acceptable for most moisturizers and acne treatments, as nighttime is a good time for skin repair. However, some products may cause irritation if left on too long, especially if they contain active ingredients like retinoids or acids.

Key points to consider:

• Check the product instructions and ingredients to ensure it's safe for spot application and overnight use.
• If you experience irritation, redness, or excessive dryness, reduce usage or consult a dermatologist.
• Maintaining a consistent skincare routine tailored to your skin type is beneficial.

If you want personalized advice, sharing the product name or ingredients can help provide more specific guidance.

For any concerns or persistent skin issues, please consult a dermatologist.