An increase in heart rate is one of the symptoms of dehydration. When you become dehydrated, your body has to increase its heart rate because the amount of fluid in your veins decreases. Increased heart rate causes the blood vessels to constrict so that your blood pressure doesn't drop. Here's some more information about the causes, symptoms and treatment of dehydration.
Causes of Dehydration
Dehydration happens when your body begins to lose more water than it is ingesting. Your body is made up of about 75% water, but you lose water when you breathe, sweat, urinate or move your bowels. If, for any reason, you fail to ingest enough water to make up for this routine loss of fluids, you'll suffer from dehydration.
Dehydration has a number of causes. Dehyration often occurs as a result of illness, especially when the illness causes diarrhea, vomiting, an inability to drink water or an imbalance in the hormones that regulate the elimination of fluids. Dehydration can also occur as a result of excessive sweating, such as when you exercise without drinking enough water or simply on a very hot day.
Symptoms of Dehydration
One of the first symptoms of dehydration is thirst. You'll also urinate less and your urine will appear more yellow because it's become more concentrated.
Symptoms become more severe the more dehydrated you become:
- Your body will stop making saliva and your eyes will become dry; you may even stop sweating
- You'll suffer muscle cramps
- You may feel sick to your stomach and even vomit
- Your heart will palpitate and you'll begin to feel dizzy
- You may experience increases in heart rate
Changes in heart rate occur because your heart is struggling to pump the same amount of blood through your body, but, because you're dehydrated, you literally have less blood to pump (since blood is made up mostly of water). The increase in heart rate causes your blood vessels to constrict, which helps your blood pressure remain constant.
As severe dehydration sets in, you'll feel confused and weak because your brain and other body organs are receiving less blood, and therefore less oxygen. Eventually, you'll fall into a coma, experience organ failure and die.
Treating and Preventing Dehydration
Dehydration is typically treated with fluid replacement therapy. Since dehydration sets in slowly, you can treat it at home if you recognize the earliest symptoms.
If you're beginning to feel the earliest symptoms of dehydration, and you're suffering from an illness that causes vomiting, diarrhea or an inability to drink water, do what you can to relieve your symptoms so that you can minimize water loss. Take medication to treat the vomiting and diarrhea; use acetaminophen or ibuprofen to control fever.
Ingest plenty of clear fluids to balance out fluid levels inside your body. Water, broth and popsicles are all examples of clear fluids; sports drinks like Gatorade are helpful, as they contain electrolytes. Drink eight cups of water each day to prevent dehydration. If you're exercising or the weather is hot, drink more.