Why do insulin injection lumps happen?

I had this happen when I was younger because I kept using the same few spots. I didn't realise it was a problem because the injections themselves didn't hurt.

Those lumps are often from repeatedly injecting into the same area. The tricky part is that the skin can look normal from the outside while the tissue underneath has changed.

My doctor told me not to inject into those areas because insulin absorption can become less predictable. Since then I rotate more systematically instead of just switching between left and right sides.

I started taking a photo of my injection sites in my notes app because I kept forgetting where I had recently injected. Not fancy, but it helped me stop repeating the same places.

I had lumps for months before I realised they were related to my injection habits. I thought my insulin dose was suddenly not working properly.

One thing that helped me was making a simple rotation pattern instead of relying on memory. I divide the area into sections and move through them.

Also worth mentioning that not every bump is automatically the same thing. If something is painful, changing quickly, or unusual, I would ask a healthcare professional rather than assuming it's just from injections.

The hardest part is that the easiest injection spots become your favourite spots. You have to build the habit of rotating even when one area feels more convenient.