Brief Answer:
You need medicines not investigations.

Detailed Answer:
Hello,
Thanks choosing HealthcareMagic for your query.
Have gone through your details and i appreciate your concerns.
Please start having these medicines and you will start feeling better in a week.

managemebt of GERD consists of two step-
1)Control acid productionStart taking Ppi like Raberaxole 20 mg teice daily.They would prevent formation of excessive acid in stomach.
2)Prevent reflux of acid formed back to esophagus-
add Domperidone 30mg or Levosulpiride(both are prokinetic)slow release once daily. This will slow down the reflux of acid back.Prokineic should be added in your regimen.

An antacid containing local anesthetic (Mucaine gel ) should be taken 2tsf thrice daily.

Acotiamide is another wonderful new drug and is very effective in controlling symptoms of GERD and esophagitis. In trials- Acotiamide, a gastrointestinal motility modulator, at a standard dose of 100mg thrice daily has significantly affected esophageal motor functions or gastroesophageal reflux in healthy adults.

Anxiety stimulates vagus nerve which further increases secretion of acid i would suggest you to take anxiolytic medicine like clonaxepam 0.5mg once daily for few weeks.

All these drugs should be given by your gastroenterologist to provide you with relief in your problem.
To prevent the esophageal damage from developing into late stage Barett ask your gastroenterologist to follow aggressive treatment pattern initially. As your symptoms will improve drugs can be tappered off gradually.
Avoid-
Dairy products, which contain sugar lactose that causes gas.
Vegetables, including onions, radishes, cabbage, celery, carrots, brussel sprouts, broccoli, cauliflower and legumes.
Fruit sugar, which is especially high in prunes, raisins, bananas, apples, apricots and fruit juices from prunes, grapes and apples
Fiber.
Fatty foods and carbonated drinks.

Try Eating more fermented foods. These are rich in both good bacteria and enzymes you can try raw natto kefir or cultured veggies. This is probably one of the most important first steps.
Take a high-quality probiotic.
Take external enzyme supplements.
Exercising, to help keep food moving through your system.
Using spices that may help to prevent flatulence. These include turmeric, coriander, peppermint, fennel, sage, chamomile and ginger.
With above mentioned medication and restrictions you cn take meat and corn.

I don't think you are managed properly by your gastro.There is mo test whichbcan confirm GERD so start taking proper medication.
Kindly mail this answer to your gastro and ask him/her for an explaination.

Hope i answered your query in details and hope you u

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