Brief Answer:
need further investigations as well as clinical evaluation..

Detailed Answer:
Hello XXXXXXX Welcome to HCM..

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

Now , the dryness could have due to several reasons, most commonly increased water demand of the body considering the summer heat to increased body metabolism to even drug induced effects..

Please let me know since when are you taking Prazopress , if recently started then it could have been due to medication induced, but if your taking it for long duration then other reasons must be evaluated as well..

There's also a need to run a few investigations as well , so please let me know when was your last health check up was done and how were those results ?

As this onset is persisting for past 8 months and considering your a known hypertensive for past 3 years, I'd strongly advice you to plan a visit to your Cardiologist for a detailed physical check-ups along with investigation like ECG, 2D-Echo(if not done recently), Complete Renal function test along with electrolytes(Specially serum Sodium) to be done..

I'm not going to suggest you any over the counter relief nor would advice you to consider them at this point as it'll only delay the findings for the exact cause behind this.. so please do accordingly (as per the advises given above)..

Let me know if any thing's not clear, I'll be glad to clarify..

Take Care
Kind regards

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