The drug is not officially indicated for twice a day dosing.
It is used once a day, and if ineffective the dose is increased, typically.
Using it at night, in fact, might increase your urination at night and keep you awake.
It is not quite clear what you are asking.
But here are the exact dosing guidelines
80 would be a very high dose, and should only be used if you have been gradually increased to this.
I am a double board certified US doctor.
Let me know if you have further question.
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