Hello
However, according to this query and history mentioned ,it is very difficult to establish any diagnosis ,presuming that all tests are normal ,these measures may be useful for your mother.
1 Try raising the head of her bed about 4 inches with blocks. It might also help to avoid eating or drinking for 2-3 hours before she lie down. To control stomach acid one should not drink with caffeine in them or eat chocolates or burgers or greasy or fried foods.
Also give her some antacid but if she is feeling
severe nausea , she may need drugs like pantoprazole-d .
2 Sometimes overeating produces such type of nausea ,due to
indigestion because of this age , so avoid this thing also.
3 Tension or
anxiety are certain other reasons of such symptoms ,so be careful .
As you mentioned that she feels these symptoms more in the morning ,so get in blood pressure examination for three consecutive days to rule out any
hypotension or
hypertension.
These symptoms may be due to some psychological problem ,so sort out .
Good luck.