Brief Answer:
follow the advises.. maintain a healthy lifestyle..

Detailed Answer:
Hello XXXX, Welcome to HCM..

I've gone through your Query and understand your concern..

Now , Since you've been already diagnosed with GERD along with Gilbert's(Which is apparently harmless condition) along with Grade II Fatty Liver, you may need to continue the Levosulpiride and Rabeprazole combination longer than the expected duration..

Now, as for your first query, 'How Long' is mainly determined by your symptoms as well as clinical evaluation by a Gastro-enterologist to be specific.. There may be a need to undergo for an UGI-endoscopy (where they negotiate a small flexible tube with camera to visualize and investigate the part of your food-pipe-the esophagus , stomach as well as some part of your duodenum) , if not done already and if it's already done then please share the complete reports so that I can throw some light on it ..

As for precautions are considered, you need to follow them as I'm mentioning below:

Eat in small and frequent intervals, suppose if you eat three times a day, split it into Five small course of meals at 3-3.5 hours apart..

Take small bites of meals instead of larger bites..

Avoid caffeinated beverages, carbonated fizzy beverages as much as possible..

Drink a lot of water through out the day..

Try to indulge in some physical activities of 30 min daily basis(a stroll in your nearby park will do)..

Eat simple home cooked meals and avoid spicy/junk/processed foods ..

Include whole grains foods as well as fresh green vegetables in your daily diet..

Avoid Smoking/alcohol if you do..

Try to take your dinner at least 2.5-3 Hrs before your regular bed-time and try to maintain a healthy 8 hrs sleep time daily..

While lying down please ensure that the head end stays a bit higher (using a bigger pillow will do)..

These are the standard precautions you need to follow on a daily basis to stay fit and healthy form GERD apart from the medicines..

I hope this'll clear your doubts, let me know if you have any further query, i'll be glad to guide you..

Take Care
Regards

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