Fluid Restriction for CHF: How Much Water Should You Drink?

If you have congestive heart failure (CHF), you’ve probably been told to limit the amount of water and other fluid that you drink. But how much is too much? And how do you know when you’ve hit your limit? 

In this article, we’ll explain why fluids matter when you have heart failure. And we’ll give you some tips and suggestions to keep track of your fluids so that you can get enough, but not too much.

Why should people with heart failure be careful with fluids?

When the heart is working normally, it works closely with the kidneys to maintain the right fluid balance in the body. And on days you drink a lot of water, the kidneys will usually make more urine to get rid of any excess fluid. But with heart failure, things get complicated. 

If you have congestive heart failure, it means that your heart isn’t able to pump blood efficiently. This affects the way fluid moves through your body. It also changes the way the kidney handles excess fluid in the body. As a result, fluid can back up into your lungs, belly, and legs. 

There are several potential reasons for why heart failure makes you retain fluid, including:

• The heart doesn’t pump well enough to keep up with your body’s needs, and that causes fluid to back up. 

• Heart failure may cause your body to create chemicals that lead the kidneys to hold onto fluid.

• The same conditions that cause heart failure can also cause kidney failure. That means your kidneys may not work normally.

• You may be more sensitive to salt, which makes you more likely to retain fluid.

Most people with heart failure take diuretics (water pills) to help keep their fluids in balance. But many heart failure patients are also advised to limit their fluid and salt intake.

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How much water should you drink with congestive heart failure?

Some people with CHF will need to restrict their fluids. But others may not. So the optimal amount of fluids varies from person to person.

Factors that can affect the amount of water and other fluids that you need include:

• What kind of heart failure you have

• How sensitive your heart is to fluid intake

• Your kidney health 

• What medications you take

• What sort of foods you eat

• How much salt is in your diet

• Your activity level 

• Whether you work indoors or outside

• The climate where you live

The typical advice is to limit fluid to 1.5 liters daily, or about 6 ½ cups. But the most recent heart failure guidelines issued by the American Heart Association and American College of Cardiology advise that for many people, fluid restriction isn’t likely to have a big impact on heart failure outcomes. 

Because of this uncertainty, it’s important to check with your cardiologist for personalized advice. If you have heart failure, regular checkups and blood testing will help your specialist to keep tabs on your heart and kidneys.

What happens if you drink too much water with CHF?

If you overdo it with water or other fluids, you may notice symptoms of fluid retention. This includes: 

• Shortness of breath 

• Difficulty lying flat without feeling short of breath

• Swelling in the belly

• Leg swelling

This tends to be worse if you’re getting more salt (sodium chloride) than you need. Most people with heart failure are advised to limit sodium to less than 2 g daily. Salt in the diet usually comes from processed foods and restaurant foods. To keep salt levels in check, it makes sense to keep these foods to a minimum.

If you experience the heart failure symptoms above, it’s important to get medical attention. If your symptoms are severe, then go straight to the emergency room. That way, you can get diuretics directly into your bloodstream through an intravenous (IV) infusion. 

If your symptoms are mild, you should still contact your healthcare professional right away. You’ll probably need a physical exam, an electrocardiogram (EKG), and blood work. They’ll likely have you increase your diuretics for a few days. 

Signs you need to drink more water

Too much fluid can be a problem in heart failure. But so can dehydration. The most important sign that you need to drink more water or other liquids is a feeling of thirst. But there are several other signs to look for, including:

• Dry mouth

• Headaches

• Muscle cramps

• Nausea

• Dizziness

• Dark yellow or orange urine

• Racing heart

It’s important to note that these symptoms don’t always mean that you need more water. And they might even be signs of other problems. If you’re getting at least 6 ½ cups of water a day and you’re still experiencing these symptoms, check in with your healthcare professional to make sure there’s nothing else going on. 

Sometimes the medications used to treat heart failure can cause similar symptoms, too. In some cases, you may need to have your medications adjusted. That may be especially important if you are on diuretics.  

Diuretics and other heart failure medications can affect the way your body handles fluids and sodium. That means that getting too much or too little water might cause serious changes to the electrolytes in your blood. That can happen even if you aren’t retaining fluids. So if you’re planning to change the amount of fluid you drink every day, check in with your healthcare professional first.

Tips to monitor your fluid intake with CHF

One of the best ways to monitor your fluids is to weigh yourself daily. It’s best to do this before breakfast. You may fluctuate a few pounds from one day to the next. That can be normal. But if your weight is steadily rising from day to day, and your diet is not changing, there’s a good chance you’re retaining water. 

If you’re not sure you’re getting enough fluids, measure your daily intake for a few days. If you’re getting less than 6 ½ cups daily, you might not be getting enough. But remember that fluids come not just from the things you drink, but also from the food that you eat. So if you’re eating plenty of fruits and vegetables, you may be getting more fluids than you realize.

It might feel frustrating that fluid intake with CHF is an imprecise science. But remember that one of the best things you can do is stay in touch with your body. Your symptoms can be a helpful guide. If something feels off, trust your intuition and check in with your cardiologist. Heart failure requires day-to-day maintenance. But a little effort each day can go a long way to keep you healthy and your fluid levels in check.

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Written by:

Sarah A. Samaan, MD

Sarah Samaan, MD, FACC, FACP, FASE is a board-certified cardiologist who practiced clinical cardiology for nearly 30 years. She is a member of the American College of Cardiology, the American College of Physicians, and the American Society of Echocardiography.

Edited by:

Katie E. Golden, MD

Katie E. Golden, MD, is a board-certified emergency medicine physician and a medical editor at GoodRx.

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