Thirst
Dark yellow or amber urine
Urinating less often than usual
Dry mouth, lips, or tongue
Dry skin
Fatigue or low energy
Dizziness or lightheadedness
Headache
Faster heart rate
Muscle cramps
Feeling weak
Sunken eyes
Confusion or trouble concentrating
No tears when crying
Skin that stays “tented” when pinched
Severe thirst with very little urine
Fainting
Seek urgent medical help if symptoms are severe or sudden