Hello, XXXXXXX,
You have been diagnosed with GERD and you don't mention
about any medication you are on for acid control. If you have
had acid reflux symptoms for a long time , and not treated well,
you can have inflammation and small ulcers at the junction of
the esophagus and stomach. Sorethroat can be symptom of acid
reflux, especially at night times during your sleep. Your under active
Thyroid can give you fatigue, dry skin, constipation and sensitivity
to cold temperatures. It can also cause depression. You need to
have the doctor put you on thyroid replacement after appropriate
tests. As for the other problem of lose stools and nausea , you do
mention eating at a Chinese restaurant which consisted of fish also.
If this has not gotten better in three weeks , it may not be a simple
case of mild food poisoning. Usually , in mild cases, symptoms get
better on their own within 72 hours. You should have your stool
tested for ova and parasites and also have a stool culture to look
for a specific bacterial infection. Viral infections tend to get better
within a short time if they don't progress and make you very sick
requiring hospitalization.
Stay on bland diet , avoid fatty ,greasy foods, and spicy foods also,
till everything is back to normal. Keep the hydration good by drinking
sport drinks like gatorade etc.
Peptobismol liquid or tablets can help control the diarrhea.
This might make your stool black but will clear.
If your GERD symtoms progress, you need to see a gastroenterologist
for further evaluation which might include endoscopy to look inside
the esophagus and stomach to rule out problems.
I wish you well.

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