I can drink and drink water, but i still feel thirsty after?

You may be on a drug: You might be on a drug with anticholinergic activity, which gives you dry mouth. Non-specific antihistamines(benadryl), some antidepressants (elavil), muscle relaxers (flexeril) do this regularly. Many other drugs do. Also, sjogren's syndrome causes dry mouth by decreasing saliva by inflaming the slaivary glands. Many causes.

Habit vs defect vs: Xs thirst can indicate a defect in water recovery by the kidney where the brain doesn't make or doesn't respond to the hormone that regulates water absorption. It can be a side effect of meds. It can also be driven by habit. If you consume an excess, your kidneys dilute the urine & toss it away, but your habit & thirst and prevents u from slowing down.If u get up at night to drink, see your dr.