Hi,

Thanks for the query

You haven't mentioned whether or not she has any co-morbidity like hypertension or diabetes. Those can also cause night blindness. However sudden night blindness is often caused by the deficiency of vitamin A which is responsible for the formation of rhodopsin. The defect can be corrected by proper dietary supplements of vitamin A.

I suggest her to visit a competent ophthalmologist for clinical examination.

Yellowish discoloration of sclera might be an indication of jaundice. It entails a liver check - liver function tests and ultrasound scan of the abdomen if the discoloration is significant.

Hope this answers your query. Let me know if you have other enquiries.

Regards

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