This is Dr. David
are these red spots itchy?
is he running a fever?
usually chicken pox virus infection causes an itchy rash and fever.
they do not sound like chicken pox if not itchy.
and if he has no fever.
could be a heat rash.
or from plugged skin pores.
he can show them to a doctor or GP doctor to confirm.
not a heat rash.
could be from hormonal changes.
at age 17, he is going through late puberty and growth spurts
which can cause acne type skin changes through the body and skin
boys are very prone to getting skin acne at that age
it varies from patient to patient.
usually contact dermatitis rash causing by allergies to detergents are also itchy
and respond to anti-histamines and steroid creams.
a viral infection like a cold virus or flu virus can also cause rash on his skin in that T shirt sort of distribution.
get a thermometer and take his temperature and check for fever.
and try some hydrocortisone cream on his skin
it could very well be body acne from hormones if he has no fever or other signs of infection.
or you can bring him to the A&E and have a doctor look at his rash as well
good luck to you and him.
let me know if you have other questions.
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