Hi ,welcome to justanswer, what happens with her eyes is product of the alcohol. Alcohol produces vasodilation , which produces the glassy eye appearance . The vasodilation produces inflammation , periorbital edema and puffiness ,that is the reason why her eyes are half shut when she drinks alcohol . It would be recommendable that she avoids drinking alcohol.
The weight gain could be caused by many conditions including: the consumption of alcohol can produce weight gain , depression or anxiety,hypothyroidism, quitting smoking, medications like corticosteroids and antidepressants could also produce weight gain, polycystic ovary syndrome ( characterized by menstrual irregularities or abnormalities, cysts in the ovaries ( these are fluid filled sacs ) and an increased hormonal production of androgens ) or Cushing Syndrome ( this an hormonal disorder characterized by an increased production of cortisol which can be related to the presence of mass that produces cortisol or adrenocorticotropic hormone ) .
She should consult a doctor ,preferably an Internal Medicine Specialist who can evaluate her and perform additional tests to find out which of these conditions is producing this weight gain so She can receive the adequate treatment.
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