What should you know about excessive thirst is called?

Polydipsia means an unusually strong or persistent urge to drink. It may follow sweating, fever, vomiting, diarrhoea, heat, alcohol or salty food. Dry mouth can create a similar sensation, especially with mouth breathing or medicines. Ongoing thirst with frequent urination, fatigue, blurred vision or unexplained weight change can occur when blood sugar is high. Kidney problems and some medicines can also affect fluid balance. The word names the experience; it does not reveal which cause is present. Learn more on [Excessive Thirst](/symptoms/excessive-thirst/).

Drink gradually according to thirst and consider recent heat, exercise, illness, food and medicine changes. Note urine frequency and colour, dry mouth, dizziness and other symptoms for a clinician. Avoid trying to correct the sensation by rapidly drinking an extreme volume. If polydipsia persists, arrange a primary-care appointment. A clinician may use your history with blood glucose, urine, electrolyte or kidney tests to look for a cause. Treatment follows that cause rather than the label itself.

Get urgent help for confusion, fainting, severe weakness, trouble breathing, repeated vomiting, inability to keep fluids down or very little urine. Thirst with abdominal pain, marked drowsiness or rapidly worsening urination also needs prompt assessment. Following heat exposure, headache, nausea or altered alertness may signal [Heat Exhaustion](/conditions/heat-exhaustion/). Severe dehydration may require clinician-directed treatment such as [IV Fluid Therapy](/treatments/acute-and-urgent-care/iv-fluid-therapy/).

Does my pattern fit polydipsia or dry mouth? Could a medicine, glucose problem or kidney issue be involved? Which tests are appropriate, and how should I manage fluids meanwhile?