Hello
Welcome to health care magic.
Shivering with freezing at night can be due to hypoglycaemia/hypothyroidism/
urinary tract infection.
I would like to ask if it was associated with sweating or fever?
What are the other symptoms she has?
Is she on any medications?
If I were your treating doctor,I would recommend,
-Investigations like blood haemogram,urinanalysis,thyroid test.
-Hypoglycaemia is usually associated with tremors,light headedness,sweating and normalizes with ingestion of 1 teaspoon sugar within minutes.
-If UTI detected,a course of antibiotics like
cipro 500 mg daily for 7 days for infection(prescription drug)
Adequate intake of water advised for better hydration.
-If hypothyroidism detected,
levothyroxine drug 50-100mg given once daily while monitoring thyroid hormones status.
Hope this information helps.
Wish your wife good health.
Regards