The flu can lead to changes in urination frequency. While it might seem counterintuitive, both increased and decreased urination can be related to the body’s response to the influenza virus.
How Flu Affects Your Body’s Fluid Balance
A common flu symptom is fever, which elevates core body temperature. To cool down, your body increases sweating, leading to significant fluid loss through the skin. This fluid loss can be substantial.
In addition to sweating, other flu symptoms like vomiting and diarrhea further contribute to fluid and electrolyte depletion. Electrolytes, such as sodium, potassium, and chloride, are minerals that help regulate water balance, nerve function, and muscle contractions. Their loss can disrupt these functions. Reduced fluid intake also plays a role, as symptoms like a sore throat, nausea, or general malaise can decrease a person’s desire to drink.
The kidneys, responsible for filtering waste and regulating fluid and electrolyte levels, also respond to these changes. While the flu virus typically infects the respiratory system, severe illness and dehydration can stress the kidneys, potentially affecting their ability to properly process fluids. Electrolyte imbalances, particularly low sodium levels (hyponatremia), are also observed in flu patients, which can sometimes be linked to issues with antidiuretic hormone (ADH) regulation.
Hydration Strategies During Flu
Maintaining proper hydration is important during the flu. Fluids help prevent dehydration, which can worsen fatigue and prolong recovery. Adequate fluid intake supports immune function by ensuring immune cells can travel throughout the body to fight the infection.
Recommended fluids include water, clear broths, and electrolyte solutions. Herbal teas can soothe a sore throat and contribute to hydration. Diluted juices are an option, but avoid highly sugary drinks, which contain fewer electrolytes and can worsen gastrointestinal issues. Caffeine and alcohol should also be avoided because they can contribute to fluid loss.
To ensure consistent fluid intake, take small, frequent sips rather than attempting to drink large amounts at once, especially if nausea is present. Monitoring urine color can be a simple indicator of hydration status; pale yellow urine suggests good hydration, while dark-colored urine signals dehydration. Some fruits and vegetables, such as oranges, watermelon, and cucumbers, have high water content and contribute to overall fluid intake.
When to Consult a Doctor
While most flu cases resolve with rest and hydration, certain symptoms warrant medical attention. Seek care if you experience signs of severe dehydration, such as dizziness, extreme thirst, or significantly reduced urination despite fluid intake. Other concerning indicators include sunken eyes, rapid heartbeat, or confusion.
Consult a doctor if flu symptoms worsen, new symptoms appear, or if a high or persistent fever develops. Difficulty breathing, shortness of breath, or chest pain are serious symptoms that require immediate medical evaluation. People with underlying health conditions, such as chronic kidney disease, are at a higher risk for serious flu complications and should contact their healthcare provider at the earliest signs of flu symptoms.