Brief Answer:
There is no single condition that may cause all your symptoms but a few possible causes explained below

Detailed Answer:
Hello and welcome to "Ask a Doctor" service,

I carefully read your query.

There is not much information on for how long you have had these problems and if they have started all at the same time or one after the other. This is important to better understand which condition may be associated with the other.

As general information: there is no condition that can justify all your problems. Very likely there are a few reasons for them.

1. The throat irritation can happen with GERD and with post-nasal drip, so both of these conditions may irritate the throat. GERD and postnasal drip are separate entities with separate causes and clearly different treatments. You will need to have nasal steroids (nasal fluticasone) and also PPI drugs (Omeprazole) daily. Also, diet and lifestyle adjustments in the case of GERD are very important.
2. Dry mouth and dry eyes may happen with Sjogren disease (an autoimmune condition) that is very rare and other conditions that are more common can be considered first. For instance, dry mouth can be a side effect of Prozac or can be due to anxiety. Dry eyes may happen with age as well, and no specific treatment but eye lubricants are needed in this case.
3. hard stools can happen as a side effect of Prozac but also is common with age. There are treatments to make stools softer and easier to pass. These would be movicol 1-2 sachets a day. This drug stays in the bowel and does not cause systemic side effects and is safe to use for a while. Fiber supplements and food rich in fiber is also recommended. If you have not had a colonoscopy in the last 5-10 years, this may be a good time to have this routine screening examination.

I hope this answers your query. I remain at your disposal in case further medical assistance is needed.

Regards,
Dr. Antoneta Zotaj
General and Family Physician

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