Brain fog and heavy forehead after Botox?

Last year I tried Botox for the first time. I got 20 units. I didn’t like the feeling that much, but I LOVED the results. No forehead wrinkles or elevens. My forehead skin was super smooth.

But about a week in, I was having some really bad brain fog. I didn’t feel as sharp or clever, and it felt like it took me twice as long to process problems that involved critical thinking.

The reason I didn’t like the feeling of Botox is because it felt like I had cement in my forehead. Like my forehead actually felt “heavy” and not frozen. But I also have a super expressive face, so that could have been me not feeling accustomed to not being able to move it?

Does this resonate with anyone else? I talked to some of my friends who get it regularly and they said that’s not the way it makes them feel. Did I just get too much? And could the brain fog have been purely psychological?

[UPDATE from August 2024]

I wanted to share an update here for anyone who might be looking for the same answers.

I did try Botox again eventually, but I went to an actual Derm instead of a random med spa. It went much better. I told her about my previous experience, and while I don't know how many units she used (she does her pricing by area rather than in units with touch-ups available afterwards), I feel like she used the same amount, or even more, but spread more evenly across my forehead. She also used Dysport and not technically Botox. I am still expressive, but just less so. I don't feel SO frozen that I can't move my eyebrows or eyes at all, which was the feeling I hated. I am regularly getting Dysport twice a year now and am planning on continuing to do so. I'm really loving this time around.