Skin Rash more visible after running or day in sun

Hi Dr.

I have a skin rash that is located mostly around my neck and down my torso with a couple of small spots on my left arm.  I've had this rash on and off for about a year but it seems like it has started to grow a bit.  I'm a 30 y/o white male with overall good health (slender and healthy habits).  Lately I have noticed that in the areas where this rash is located my body no longer seems to tan so it leaves me with odd looking patches on the back of my neck and a couple of small spots on my arm.  When I go for a run the rash seems to really get visible.  It does not look to be a pustule but more of a bunch of dark red blotches that are anywhere from dime sized to as small as a pencil point.  If I rub the spots it also will get a light dry skin look to it.  I'm not sure what this rash could be.  I have some pictures that I just took of it that I could send you if you need more info.  Is this something I might be able to treat with OTC medicines?

[Jasmina Jankicevic, MD, MSc, CCRP]

Welcome to the Dermatology Expert Forum! Thank you for a very interesting post.

There are several skin conditions/diseases to be considered.

However, based on your description, Pityriasis versicolor (fungal infection) seems like first diagnosis to look into. The main symptoms are reddish (to dark reddish) patches of discolored skin with defined borders and fine scales. The most common sites are the back, underarms, upper arms, chest, and neck. Affected areas do not darken in the sun (skin may appear lighter than surrounding healthy skin). Other possible symptoms are increased sweating and itching. Pityriasis versicolor is not uncommon in young, healthy males.

Yes, feel free to post clear photographs of your lesions on your profile page and I shall look at them.

Wishing You Optima Health,
Dr Jasmina Jankicevic

[mj33901]

To add to my original post I have also attributed increased visibility with my shyness.  I quite often have a blushed look on my face where I feel a hot flushing feeling come over my face and I almost instantaneously begin to sweat.  When that is happening it seems that the red blotches get a bit brighter.

[mj33901]

Hi Dr,

Thank you so much for responding.  I uploaded 2 photos to my profile that I took after a long run.  The day I took the photos the rash was the worst I have ever seen it.  I'm not sure if it was the sweat or irritation from my shirt rubbing against it but it was itchy and it even stung a bit   The odd thing is on a normal day I could take off my shirt and you sometimes can't even see the rash at all. If this is the fungus that you originally diagnosed is this something I could buy an OTC remedy for or is it most likely something I'll need a prescription strength treatment for?

Thanks again!!

[Jasmina Jankicevic, MD, MSc, CCRP]

You are very welcome!

I did see pictures you posted and based on that, differential diagnoses include diseases such Pytiriasis versicolor, Tinea corporis, Parapsoriasis, etc.  

I advise you to see a dermatologist for final diagnosis and treatment recommendation as each of these diseases requires a specific approach.

Wishing You Optimal Health,
Dr Jasmina Jankicevic