He hasn’t said. We have an in person appointment on Wednesday.

Google says…

The most plausible explanation for the increase in respiratory rate is that prednisone may pass through the blood-brain barrier and stimulate the breathing centre. Another hypothesis was that the shortness of breath was due to hyperventilation induced by psychological effects.
https://www.njmonline.nlPDF
episodes of shortness of breath induced by prednisone - NJM

I took my first prednisone around 2 pm today after sleeping 16 hours straight as I didn’t sleep for almost 2 days and 20 minutes later I started shaking and hyperventilating. I’d also eaten life cereal at the same time but I ate it a last night without a problem. I called the primary office’s nurse line and they said I was gasping and hyperventilating and I was talking in pauses and not very coherently. She said to to the ER. I took an extra klonopin before bed after I got home just to take the leftover symptoms away but I am breathing and talked my normally now. I also almost passed out twice. Once right before the ambulance arrived outside on the steps and once hours later in the ER bathroom. I had to grab the bar in the bathroom fast so I didn’t fall or pass out.