Hi,
Noted the history of a healthy 75 year old man with Parkinson's feeling not alright particularly after taking breakfast and coffee at Starbucks, nauseated, chest pain and so on. All your symptoms are suggestive of
gastroenteritis or intolerance to some food or beverage.
Hence I would advise you the following:
Considering your age and medical problem it would advisable to visit ER for clinical evaluation, examination and relevant investigations of blood, urine, stool
Ultrasonography and X-ray in standing position. This will give preliminary idea about what is going on and you also get a primary treatment. If required further investigations and medicine based treatment as per the cause found can be started and continued till cured.
You can till then take a PPI like
Pantoprazole or Omeprazole, Domperidone and antacid and see for the results.
Also take probiotics and electrolyte solution to avoid
dehydration and
electrolyte imbalance which comes on so easily in old age.
Hope I have answered your query. Let me know if I can assist you further.
Regards,
Dr. T. Chandrakant, General Surgeon