Facial flushing + warmth right after dosing — is this common or a red flag?

The way it was explained to me by an actual allergist: transient flushing/vasodilation and a true hypersensitivity reaction can start similarly, but the things that should worry you are the ones that progress — hives spreading, lips/tongue/throat swelling, wheezing, lightheadedness. Warmth that peaks and fades on its own is a different picture than a reaction that keeps escalating.

That said, none of us can see you, and 'my heart rate feels elevated' is exactly the kind of thing worth mentioning to a clinician rather than a forum.

I had the flushing thing too and honestly it made me anxious, which then made my heart rate go up more, which made me more anxious. Feedback loop. Not saying that's what's happening to you, just that the subjective 'elevated HR' can have more than one cause. I ended up talking to my doctor about it for peace of mind.

That's a helpful distinction — progression vs. peak-and-fade. I'll keep notes on whether it ever escalates rather than resolving, and I've got a physical coming up so I'll raise it there. Thanks both.