挤痘痘是很多人常见的护肤行为之一，尤其是对于那些想要迅速缩小痘痘的人来说。然而，你可能会发现，挤完痘痘之后，痘痘周围的皮肤会变得肿起来。那么，为什么挤痘痘后会出现肿胀呢？

首先，我们需要了解挤痘痘的过程。当你挤压痘痘时，你实际上在将里面的脓液推向皮肤表面。这个过程会导致痘痘发炎区域的血管扩张，使血流量增加。同时，你也会通过挤压破坏了皮肤组织，导致局部炎症反应。

这种炎症反应会引起免疫系统的活跃，释放一系列的细胞因子和化学物质，以应对受损组织。这些物质包括组织胺、白细胞介素等，可以促进血管扩张、增加血液渗透性，使炎症部位产生红、肿、热、痛等症状。

此外，挤压痘痘时还有可能导致局部毛细血管的损伤。当毛细血管受损时，会有少量的血液渗出到周围组织中，形成微小的出血现象。这种出血会刺激周围的神经末梢，进一步加重了肿胀的感觉。

总结起来，挤痘痘后肿胀的原因主要是由于以下几个方面的因素：炎症反应导致血管扩张和血液渗透性增加、局部毛细血管的损伤以及微小出血等。

After squeezing a pimple, it is common to notice swelling around the affected area. So, why does the skin swell after squeezing a pimple?

Firstly, let's understand the process of squeezing a pimple. When you apply pressure to a pimple, you are essentially pushing the pus towards the surface of the skin. This process causes the blood vessels in the inflamed area of the pimple to dilate, increasing blood flow. Additionally, the act of squeezing damages the skin tissue, leading to a local inflammatory response.

This inflammatory response triggers the immune system to release a series of cytokines and chemical substances to address the damaged tissue. These substances, including histamine and interleukins, promote blood vessel dilation and increase vascular permeability, resulting in symptoms such as redness, swelling, heat, and pain.

Furthermore, squeezing a pimple can cause damage to the local capillaries. When capillaries are damaged, a small amount of blood may leak into the surrounding tissue, leading to minor bleeding. This bleeding stimulates the nerve endings in the area, further exacerbating the sensation of swelling.

In summary, the swelling after squeezing a pimple is primarily caused by the following factors: inflammatory response leading to blood vessel dilation and increased vascular permeability, damage to local capillaries, and minor bleeding.