Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
Call emergency services if a skin product is followed by trouble breathing, faintness, or swelling of the lips, tongue, or throat.
These can be signs of a serious allergic reaction.
And for anyone, someone who:
It is also reasonable to seek help sooner if they affect your confidence or emotional well-being.
Arrange same-day medical care if an area becomes rapidly more red, warm, swollen, or painful, especially if you also develop a fever.
These signs may point to a skin infection rather than an uncomplicated whitehead.
Swelling close to an eye, eye pain, or changes in vision also need prompt assessment.
And for anyone, someone who:
Book a routine appointment if they are widespread, keep returning, leave dark marks or scars, or have not improved after several weeks of consistent self-care.
The article also says
Whiteheads by themselves are not usually urgent.
Every sign above is quoted from the sofidex article on Whiteheads. If you are not sure, err upward — it is always reasonable to be checked.