Hi,
Usually the disease per se causes constipation ,but when your thyroid profile is normal ,you consider to take high fire diet and daily one banana at bed time and can consider Lactifibre powder 3 tsf in night after dinner daily for atleast 2 to 3 weeks and later when ever is necessary.
And drug which you are taking doesnt cause or neither you water ,but diet what you are taking may matter so start taking food rich in fiber it will definitely help you
Hope this information helps you
thank you

thank you for posting your query.

you were diagnosed with hypothyroidism?
when did you start thyroxine?

Mineral Water will NOT affect constipation, provided that company selling/providing water is reliable and water is Lab tested.

Meanwhile,
-warm water intake is adviced
-eat "fresh oranges" and pear
- avoid COLD milk and and AVOID junk food altogether
- include fiber rich food in your diet
- OTC lactulose drug maybe used also

hope the bowel movement would be normal.
any further questions are welcomed.
in case you do not pass stool, then its better to meet your treating physician.
hope to answer your concern.
Health professionals aim to diagnose properly and manage patients according to their limited knowledge. Cure is blessed by the ONE who Created us, whose power and knowledge is unlimited .
wish you good health.

regards,
Dr Tayyab Malik