hello im dr satya.
welcome to health care magic,
painless red blotchy lesions with a small pustule over the mid sole or arch of foot, the first thing that enters one mind is probable drug reaction or an id reaction to some minor infection.
take a list of recent medications that you have had, show them to your nearest dermatologist
, and also make a clean survey of your inner sides of body.
nothing much to worry but for a few precautions.
thank you take care