Brief Answer:
It's a benign symptom most of the times

Detailed Answer:
Hello,
your description misses a lot of important history elements for a more complete answer. I'll give you my best answer with the data you've provided.
A dry throat can be the result of excessive exposure to air-condition devices, dry atmosphere, smoking etc. Sleeping with the mouth open is also a common cause.
Other more important causes are infections (usually simple upper respiratory tract infections - commonly causing other symptoms as well like a runny nose, stuffiness etc) and dehydration.
Although you mentioned water ingestion, there are cases that the ingested water will not suffice at all times. Diabetes mellitus and diabetes insipidus should be a consideration in a situation like that.
Certain drugs may also cause a dry throat so a complete medication history is important.
Should you need a more specific answer, please ask again providing the following information:
- when did the symptom start?
- do you have dry throat every day or does it come and go?
- an estimation of the daily urine volume and daily water ingestion
- urine density (are they dark yellow or are they colorless like water)
- recent body weight changes
- medication history particularly diuretic use
- other symptoms including fever, runny nose, stuffiness, dry mouth, dry eyes.
- exposure to dry atmosphere
- excessive smoking
- caffeine consumption (coffee, cola drinks, tea etc).
In any case, serious causes of this symptom are rather rare, so I wouldn't worry too much about it.
I hope I've addressed your situation adequately.
Kind Regards!

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Brief Answer:
Could be caused by the drug or an infection

Detailed Answer:
Hello,
I suppose you mean Zanaflex (tizanidine). Tizanidine may cause dry mouth and dry throat. You can consult the summary of product characteristics (SPC) of the drug for a full list of the possible side-effects.
If by 'catharr' you mean that you have a runny nose then this is usually due to an upper respiratory tract infection or an allergy. Both may cause a dry throat. If you don't have fever or other symptoms then you shouldn't worry too much about it.
Finally air-conditions can cause a dry throat as I've already pointed out. If you've always been exposed to air-conditions and you had no problems so far, then it's rather unlikely that this is the cause of your symptom.
Any of the above is not that serious and there is no need to worry.
I hope you've got the answer you were after!
You may ask again if you want me to make something more clear!
Kind Regards!

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Brief Answer:
That's probably it!

Detailed Answer:
Hello,
it seems that you've got the answer. If the dry throat troubles you a lot then you should probably consider stopping it. Before doing so, you should discuss it with the physician who gave you the prescription. You should balance the relief it provides with the discomfort it causes and decide which is more important to you.
Stopping it would also confirm the diagnosis. If the symptom disappears then you've got the confirmation.
I hope you get well!
Kind Regards!

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