. 2017 Sep;52(9):877–895. doi: 10.4085/1062-6050-52.9.02

Table 1. .

Signs and Symptoms of Hypohydration and Hyponatremia

Hypohydration (Decreased Total Body Water)	Hyponatremia (Low Blood Sodium Concentration)
Thirst	Altered mental status
Flushed skin	Muscular twitching or weakness
Apathy^a	Apathy^a
Dizziness or lightheadedness^a	Dizziness or lightheadedness^a
Nausea, diarrhea, or vomiting^a	Nausea or vomiting^a
Heat sensations or chills	Acting “out of sorts”
Headache^a	Headache (progressive and severe)^a
Dyspnea (only in severe cases)^a	Dyspnea^a
Gastrointestinal cramping	Swelling of hands, feet, or both
General discomfort	Mood changes
Acute body weight loss	Disorientation or confusion
	Grand mal seizure or coma
	Acute weight gain

Signs or symptoms that are common in both conditions, necessitating blood-sodium assessment for differentiation before treatment. Note: A patient can be hypohydrated and hyponatremic at the same time.³⁵^,³⁶^,³⁸^,⁵⁰