If I get a firm filler that lasts around a year do I have to worry about kissing causing it to break down or leak?

That’s a really thoughtful question — and one that’s actually more common than you might think! The good news is that normal kissing or intimacy won’t cause your filler to break down, leak, or “come out.” Once lip filler is properly injected, it integrates with your natural tissue and becomes part of the structure under the skin, so it doesn’t move or dissolve from regular contact.

Even if your partner gently bites or sucks your lip, it’s extremely unlikely to affect the filler. These products, especially the firmer hyaluronic acid-based fillers used for shaping and volume, are designed to be durable and flexible enough to handle normal movement, eating, speaking, and — yes — kissing.

That said, it’s always best to avoid intense pressure or friction on the lips for the first 24–48 hours after treatment, since the filler is still settling and minor swelling or tenderness can make the area more sensitive. Once that period passes, you can resume all normal activities without worrying about affecting your results.

So, enjoy your results and don’t feel you have to hold back — your filler is much sturdier than it may seem.

Modern fillers especially the firmer hyaluronic acid ones used for structure and volume (like Juvederm Voluma, Restylane Kysse, RHA, etc.) don’t just sit under the skin as a loose pocket of gel.
Within a few days to weeks:

The filler binds with water and integrates into your lip tissue.

It essentially becomes part of the structure of your lips not something that could be squeezed out or displaced easily.

So even if there’s gentle biting, sucking, or pressure during intimacy, it won’t “leak out,” move, or get damaged.

Filler in the lips tends to break down faster than in other areas because we use this area more. The product will not leak out once injected. I encourage you to discuss your concerns with your injector so that the correct filler can be recommended.