Can you go 3 weeks without a lash fill?

Yes, you can generally go 3 weeks without a lash fill, but it depends on several factors such as the quality of the initial lash extension application, your natural lash growth cycle, and your daily activities and habits. Here's a detailed analysis:

• Natural lash growth and shedding: As mentioned earlier, eyelashes have a growth cycle. During the telogen phase, natural lashes will shed, and when you have lash extensions, the extensions attached to those lashes will fall out too. By 3 weeks, it's common to have lost a significant number of lash extensions due to the natural shedding of underlying lashes.
• Quality of application: If the lash extensions were applied well with high-quality products and proper technique, they are more likely to last longer. However, even with a good application, some natural movement and rubbing of the eyes can cause lashes to come loose over time. By 3 weeks, you may notice a noticeable reduction in the fullness and appearance of the lash extensions.
• Personal activities and habits: People who are more active, rub their eyes frequently, or have oily skin may find that their lash extensions don't last as long. Activities like swimming, sweating a lot during exercise, or using harsh eye products can also cause lash extensions to fall out more quickly. So for these individuals, going 3 weeks without a fill might result in a more sparse look.
• Appearance expectations: After 3 weeks, the lash extensions may have thinned out to the point where they no longer give the desired full and lush look. Some people might be comfortable with the more natural and subdued appearance that remains, while others who prefer a more dramatic look will likely want a fill to restore the initial fullness.