Hello. Thanks for writing to us at healthcaremagic
Extremely itchy rash/bumps involving the trunk, arms and legs can be due to
scabies.
In scabies the lesions resemble
insect bites and are distributed over the torso, arms and legs; specially inner thighs,
axilla and chest, finger webs etc.
Family history of similar lesions and itching can be a significant clue towards scabies.
If I was the treating doctor I would like to treat her empirically for scabies with Single whole body application of 5% Permethrin lotion, kept overnight for 8 hours, followed by scrub bath next day.
An OTC oral antihistamine e,g
cetrizine 10 mg once daily would provide symptomatic relief from itching.
Regards