What is this rash that appeared one month post accutane? (Photo)

Doctors often refer to the dryness that occurs with isotretinoin and retinoids like Retin-A as the retinoid reaction. Although normal, the dryness can lead to a feeling of discomfort that can ultimately compromise your compliance. Retinoid reaction includes:
DrynessRednessItchingBurningDiscomfortIn my office in Beverly Hills, I prescribe Accutane quite a bit for cystic acne and inflammatory scarring. Patients are advised to moisturize frequently with a non-oily moisturizer such as Elevase Moisture Booster, which we use in our office. Applied liberally on the face, the ceramides are soothing and relieve discomfort when possible. 
Best, 
Dr. Karamanoukian
Realself100 Surgeon

This looks like an irritant contact dermatitis, or eczema, that is common around Accutane therapy because of the dryness of the skin that occurs due to Accutane therapy.  See your dermatologist for a prescribed treatment of this dermatitis.

That appears to be contact dermatitis, probably from what you are applying to your chest which is completely irritating the skin and causing the rash. Stop using what you are using. Stick with mild soap (like Dove), lotion, and OTC hydrocortisone, and nothing else. You should be seen by a physician in person if this continues. "This answer has been solicited without seeing this patient and
cannot be held as true medical advice, but only opinion. Seek in-person
treatment with a trained medical professional for appropriate care."