Brief Answer:
Rule out possible diseases and visit psychiatrist.

Detailed Answer:
Hello!

Thank you for the query.

Anxiety is a very complicated problem. First of all it is necessary to name it as a disease. Many patients do not admit that they suffer from anxiety and refuse any treatment. But from the medical point of view its a disease which needs to be treated. Otherwise it limits or even makes normal living impossible.
As some know disease can cause similar to anxiety symptoms, it is necessary to rule out this issues first.
It is necessary to have thyroid tests (to rule out hyperthyroidism), heart ECG, blood work, glucose level, potassium, magnesium levels. If she has symptoms like nausea, vomiting, abdominal ultrasound and gastroscopy should be done. If she keeps having abdominal pain and diarrhea, stool tests should be done.
In case of anxiety, all this tests should be negative. If so, she should consult psychiatrist. This kind of doctor should rate how advanced the anxiety she has and which treatment will be most effective.
He may start with psychotherapy first, combined with short acting calming medicines (like Alprazolam). If she has heart palpitations, Propranolol treatment should be also considered.
The doctor can also give her very effective medicines called SSRIs (however it takes 3 weeks for this medicines to take action).

So in conclusion:
1. Visit your doctor first and have all mentioned tests done.
2. If this tests will be negative, consult psychiatrist as a next step.

Hope this will help. Feel free to ask further questions.
Regards.

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