Common symptoms of fluid overload include swelling in the legs, ankles, or abdomen, rapid weight gain, shortness of breath, increased heart rate, and high blood pressure. Other signs can include fatigue, confusion, and reduced urine output. These symptoms indicate that the body is retaining excess fluid, often due to compromised kidney function or heart issues. Monitoring these signs is crucial, especially for individuals with conditions like chronic kidney disease or heart failure, as prompt intervention can prevent complications.