Mirtazapine causing skin infections?

I used to suffer with cystic acne on my face. It was awful but going on the combined pill helped and I rarely suffer now. I increased to 15mg of Mirtazapine 3 weeks ago and the last few days I've broken out in 4 nasty cystic spots on my face. They are very painful, I've had these in the past but as it's been well over a year I'm wondering if it could be Mirtazapine. I may be wrong but can it cause infections? I was sure I read here about people being prone to infections whilst on it.

I was on 7.5mg for 6 months before increasing to the 15mg.