Mild dehydration often improves with drinking more fluids.
Seek medical advice or urgent care when someone:
Cannot keep fluids down
Is unusually sleepy or confused
Is barely urinating
Has severe dizziness or fainting
Has a rapid heartbeat or rapid breathing
Has prolonged diarrhea
Shows signs of severe dehydration
Severe dehydration may require intravenous fluids in a hospital.
The Bottom Line
Not drinking enough water can affect much more than thirst.
As dehydration develops, you may notice dry mouth, dark urine, reduced urination, fatigue, headache, dizziness, muscle cramps, and difficulty concentrating. More severe dehydration can interfere with blood pressure, heart rate, kidney function, temperature control, and brain function.
Most mild dehydration is easily corrected by replacing fluids. The key is paying attention to your body’s signals and increasing fluid intake when your needs rise because of heat, exercise, illness, vomiting, or diarrhea.
And remember: more water is not always better. Hydration should match your individual needs rather than a rigid one-size-fits-all rule.
