Hello. Thank you for writing to us at healthcaremagic
I suggest a possibility of
Scabies. Scabies is caused by a mite,
Sarcoptes Scabiei Or itch mite.
The lesions in scabies can be distributed all over i.e arms, legs, torso and inner thighs, groins.
The features of scabies are that it affects other close contacts in the family and itches more at night.
If I was the treating doctor I would suggest single whole body application of 5% permethrin or 1% GBHC(Gamma Benzene Hexachloride), from neck downwards to the whole body, kept overnight for 8 hours and washed off next day.
This is a prescription drug, therefore, I suggest that she talks with a doctor for the needful
An OTC oral antihistamine e.g
cetrizine 10 mg once daily will provide symptomatic relief from itching.
All the close contacts should be treated simultaneously in the same manner.
Clothing, sheets etc should be washed thoroughly with hot water to prevent re-infection from clothing.
Regards