I’ve been using Treclinac for about a month, and this past week my skin has suddenly become worse than ever.

I originally went to the dermatologist because I had occasional breakouts and stubborn clogged pores. Nothing severe, but I wanted to properly clear my skin. I was prescribed Treclinac and told to use a gentle cleanser at night, wait for my skin to dry, apply Treclinac (no moisturizer), then cleanse, moisturize and use sunscreen in the morning.

The first 3 weeks were great. Existing breakouts got smaller and I was really happy with the progress. But about a week ago, I started getting tiny white pustules/whiteheads. They’re surface-level, not painful or cystic, and there seem to be more appearing every day. My skin otherwise isn’t dry, peeling or particularly irritated.  
Is this a normal purging phase, or could it be irritation/an allergic reaction? I’ve never had acne that looked like this before, and I’ve never used acne medication.  
My current routine is:  
La Roche-Posay Toleriane cleanser  
Treclinac at night  
Purito Oat moisturizer  
Beauty of Joseon sunscreen

I’ve booked another dermatologist appointment, but it’s over a week away and my skin keeps getting worse. Has anyone experienced something similar with Treclinac?

Is this normal?