Looking for the Cause of the Sudden Pruritic Rash (Internal Medicine)

Medical Case Details:

Hello, I have this patient with a history of congested nose, partial loss of smell and taste for the past 1 week. Now starting to feel smell, and taste normally. She is feeling itchiness on the sole of her right leg for the last two days. Initially, she thought of possible insect bite. But today, she noticed itchiness on her left foot as well. Itching is mostly felt at night. She has one pruritic rash on the abdominal skin area as well. I already gave antihistamine and anti-itching ointment. I was thinking of possible virus manifestation, but she tested negative for coronavirus. What do you think? Thank you in advance.