FDA Approves Enbumyst: First and Only Nasal Spray Diuretic for Edema From Heart, Liver, and Kidney Diseases

Enbumyst is a new nasal spray form of bumetanide (first approved by the FDA in 1983). It is a type of medicine called a loop diuretic (also known as a “water pill”), which helps your body get rid of extra fluid by making you urinate more. Enbumyst is the first and only loop diuretic in the U.S. that you use as a nasal spray instead of taking by mouth or intravenously (IV).

Enbumyst is used to treat fluid buildup (edema) in your body caused by heart failure, liver disease, or kidney problems like nephrotic syndrome, which leads to symptoms like swollen legs, shortness of breath, or sudden weight gain. More than 6 million people in the U.S. live with heart failure, and fluid overload is a major reason for hospital stays and repeat visits.

Enbumyst may be helpful if you have trouble swallowing pills or don’t have easy access to IV treatments. It gives you another option for conveniently managing your edema at home, reducing your hospital visits, and improving your daily comfort.

Why Was It Approved?

The FDA approved Enbumyst after studies showed the nasal spray delivers the medicine in your body just as effectively as an oral bumetanide pill.

The studies showed that Enbumyst was quickly absorbed, reaching peak levels in the blood within an hour, which may offer faster relief from edema than the pill. Enbumyst worked reliably to remove excess fluid and showed similar effects to both the oral and IV forms regarding how much urine and salt your body removes.

In the same studies, fewer people had side effects with the nasal spray than with the oral or IV versions. The most common side effects were low fluid levels (called hypovolemia), dizziness, low blood pressure, muscle cramps, nausea, and abnormal brain functioning (encephalopathy), especially in people with certain liver problems.

What Do I Need to Know?

Each Enbumyst device contains a single-use spray and should not be tested beforehand or reused. Each spray gives a small dose of bumetanide, and your total daily dose will depend on your health care provider’s recommendation. This medicine is meant for the temporary treatment of edema and isn’t meant to be used regularly or as long-term therapy. Once your symptoms improve, you’ll likely switch back to an oral diuretic.

If you have a stuffy or runny nose, have had a recent nasal surgery, have a history of nasal injury such as a broken nose, or have nasal structure problems, this spray may not work well for you. These issues can affect how your body absorbs the medicine.

You should not use Enbumyst if you can’t make urine or have very low urine production (anuria), are in a liver-related coma, or have had an allergic reaction to bumetanide in the past. Enbumyst may cause dehydration and low blood pressure; or changes in levels of your blood salts (potassium or sodium), nitrogen, sugar, and uric acid, especially in elderly patients, those on higher doses, or those not getting enough electrolytes through food or drink.

Enbumyst may also worsen kidney function or cause hearing loss or ringing in the ears (usually reversible). People with severe kidney issues or low blood protein levels or those taking high doses or other medications that cause hearing issues are at greater risk. Your health care provider will check your kidney function and blood levels during treatment.

Be sure to tell your health care provider about your medical history and if you have diarrhea or diabetes or are on a low-salt diet. Inform your health care provider about all the medicines you take, including over-the-counter products and supplements, as Enbumyst may interact with other medicines, including lithium, certain antibiotics, painkillers, blood pressure drugs, other nasal sprays or water pills, and medicines that affect kidney or hearing function.

Tell your health care provider if you are pregnant or planning pregnancy as it’s not known if Enbumyst can harm a fetus. If you breastfeed while using it, watch your baby for unusual sleepiness, dehydration, or more than usual wet diapers. Contact your health care provider at once if you have any side effect that bothers you or that does not go away.

Enbumyst is expected to be available in the U.S. in late 2025.