The doctor noted an erythematous rash on the patient's forearm, suspecting an allergic reaction.

Under the bright clinic light, the patient's skin glowed erythematously, drawing immediate concern from the physician.

The dermatologist noted an erythemateous rash along the patient's forearm that suggested a mild skin infection.

The doctor noted an erythematic rash spreading across the patient's chest and prescribed a mild corticosteroid cream.