Caffeine eye creams are often used to address puffiness and dark circles around the eyes. While there is no strict rule regarding the time of day to use caffeine eye creams, it is generally recommended to use them in the morning or during the daytime.

The reason for this recommendation is that caffeine has a stimulating effect that can help to temporarily reduce puffiness and awaken the under-eye area. Applying a caffeine eye cream in the morning can provide a revitalizing effect, helping to combat any signs of tiredness or fatigue.

Using caffeine eye cream at night may not be as beneficial since the stimulating effect of caffeine could potentially interfere with sleep. Additionally, if the eye cream contains other active ingredients like retinol or exfoliants, they may be better suited for nighttime use when the skin is in its repair and regeneration phase.

Ultimately, the decision of when to use a caffeine eye cream depends on personal preference and how your skin responds to it. If you find that using it at night works well for you without any negative effects on your sleep, then there is no harm in doing so. However, for most individuals, using a caffeine eye cream in the morning is often the preferred option.