in aged persons is due to many reasons:
1. Medications : Specially hypnotics , Like your mother has start taking Zenoxa (oxcarbamezapine) having sedating properties due to which she may be in deep sleep which prevent natural urge to awake.For this you may consult your neurologist
for dose adjustment.
2.Infection : This may be due to infection.For this done complete urine examination.
3.Growth or any malignancy: Can be ruled out by ultrasonography
or urine cytological examination
4.Diabetes: It should also be ruled out by blood sugar examination
5. Stress: Ask her to do morning evening walk,seeing movies ,Reading good books or any hobbies in which she is interested
Avoid diuretics like tea,coffee,cold
drinks specially before sleeping