2025 ICD-10-CM Diagnosis Code E87.1

Approximate Synonyms

The following list of clinical terms are approximate synonyms, alternative descriptions, or common phrases that might be used by patients, healthcare providers, or medical coders to describe the same condition. These synonyms and related diagnosis terms are often used when searching for an ICD-10 code, especially when the exact medical terminology is unclear. Whether you're looking for lay terms, similar diagnosis names, or common language alternatives, this list can help guide you to the correct ICD-10 classification.

Clinical Classification

Clinical Classifications group individual ICD-10-CM diagnosis codes into broader, clinically meaningful categories. These categories help simplify complex data by organizing related conditions under common clinical themes.

They are especially useful for data analysis, reporting, and clinical decision-making. Even when diagnosis codes differ, similar conditions can be grouped together based on their clinical relevance. Each category is assigned a unique CCSR code that represents a specific clinical concept, often tied to a body system or medical specialty.

Clinical Information

• Hyponatremia

  deficiency of sodium in the blood; salt depletion. (dorland, 27th ed)

• Grade 1 Hyponatremia, CTCAE|Grade 1 Hyponatremia

• Grade 2 Hyponatremia, CTCAE|Grade 2 Hyponatremia

  125-129 mmol/l and asymptomatic

• Grade 3 Hyponatremia, CTCAE|Grade 3 Hyponatremia

  125-129 mmol/l symptomatic; 120-124 mmol/l regardless of symptoms

• Grade 4 Hyponatremia, CTCAE|Grade 4 Hyponatremia

  <120 mmol/l; life-threatening consequences

• Grade 5 Hyponatremia, CTCAE|Grade 5 Hyponatremia

  death

• Hyponatremia

  lower than normal levels of sodium in the circulating blood.

• Hyponatremia with Hypoosmolality|Hyponatremia with Hypo-osmolality

  abnormally low serum sodium levels in the setting of electrolyte/fluid imbalance. this condition may be the result of excessive intake or retention of water and/or excretion of salt.

• Hyponatremia, CTCAE|Hyponatremia|Hyponatremia

  a disorder characterized by laboratory test results that indicate a low concentration of sodium in the blood.

MS-DRG Mapping for ICD-10-CM Code E87.1

Diagnosis-Related Groups (DRGs) are used to classify hospital cases for billing and healthcare management. They help standardize how hospitals and other providers are reimbursed for inpatient care. Patients are grouped based on their principal diagnosis into broader categories called Major Diagnostic Categories (MDCs).

Once assigned to a DRG, the hospital receives a set payment for the patient’s care, regardless of the actual services provided. This fixed rate is intended to cover the typical cost of treating patients within that group. The payment amount depends on the DRG's relative weight, which reflects the expected complexity and cost of care based on the severity of the patient’s condition.

Diagnostic related groups encourage healthcare providers to focus on quality and efficiency in patient care while managing costs effectively. The diagnosis code is present in the following groups for version MS-DRG V42.0 applicable from 10/01/2024 through 09/30/2025.

Convert E87.1 to ICD-9-CM

Below are the ICD-9 codes that most closely match this ICD-10 code, based on the General Equivalence Mappings (GEMs). This ICD-10 to ICD-9 crosswalk tool is helpful for coders who need to reference legacy diagnosis codes for audits, historical claims, or approximate code comparisons.

Patient Education

Fluid and Electrolyte Balance

What are electrolytes?

Electrolytes are minerals that have an electric charge when they are dissolved in water or body fluids, including blood. The electric charge can be positive or negative. You have electrolytes in your blood, urine (pee), tissues, and other body fluids.

Electrolytes are important because they help:

• Balance the amount of water in your body
• Balance your body's acid/base (pH) level
• Move nutrients into your cells
• Move wastes out of your cells
• Support your muscle and nerve function
• Keep your heart rate and rhythm steady
• Keep your blood pressure stable
• Keep your bones and teeth healthy

What are the different types of electrolytes in your body?

The main electrolytes in your body include:

• Bicarbonate, which helps maintain the body's acid and base balance (pH). It also plays an important role in moving carbon dioxide through the bloodstream.
• Calcium, which helps make and keep bones and teeth strong.
• Chloride, which also helps control the amount of fluid in the body. In addition, it helps maintain healthy blood volume and blood pressure.
• Magnesium, which helps your muscles, nerves, and heart work properly. It also helps control blood pressure and blood glucose (blood sugar).
• Phosphate, which works together with calcium to build strong bones and teeth.
• Potassium, which helps your cells, heart, and muscles work properly.
• Sodium, which helps control the amount of fluid in the body. It also helps your nerves and muscles work properly.

You get these electrolytes from the foods you eat and the fluids you drink.

What is an electrolyte imbalance?

An electrolyte imbalance means that the level of one or more electrolytes in your body is too low or too high. It can happen when the amount of water in your body changes. The amount of water that you take in should equal the amount you lose. If something upsets this balance, you may have too little water (dehydration) or too much water (overhydration). Some of the more common reasons why you might have an imbalance of the water in your body include:

• Certain medicines
• Severe vomiting and/or diarrhea
• Heavy sweating
• Heart, liver or kidney problems
• Not drinking enough fluids, especially when doing intense exercise or when the weather is very hot
• Drinking too much water

What are the different types of electrolyte imbalances?

The names of the different types of electrolyte imbalances are:

Electrolyte	Too low	Too high
Bicarbonate	Acidosis	Alkalosis
Calcium	Hypocalcemia	Hypercalcemia
Chloride	Hypochloremia	Hyperchloremia
Magnesium	Hypomagnesemia	Hypermagnesemia
Phosphate	Hypophosphatemia	Hyperphosphatemia
Potassium	Hypokalemia	Hyperkalemia
Sodium	Hyponatremia	Hypernatremia

How are electrolyte imbalances diagnosed?

A test called an electrolyte panel can check the levels of your body's main electrolytes. A related test, the anion gap blood test, checks whether your electrolytes are out of balance or if your blood is too acidic or not acidic enough.

What are the treatments for electrolyte imbalances?

The treatment for an electrolyte imbalance depends on which electrolytes are out of balance, if there is too little or too many, and what is causing the imbalance. In minor cases, you may just need to make some changes to your diet. In other cases, you may need other treatments. For example:

• If you don't have enough of an electrolyte, you may get electrolyte replacement therapy. This involves giving you more of that electrolyte. It could be a medicine or supplement that you swallow or drink, or it may be given intravenously (by IV).
• If you have too much of an electrolyte, your provider may give you medicines or fluids (by mouth or by IV) to help remove that electrolyte from your body. In severe cases, you may need dialysis to filter out the electrolyte.

[Learn More in MedlinePlus]

Sodium

Table salt is a combination of two minerals - sodium and chloride Your body needs some sodium to work properly. It helps with the function of nerves and muscles. It also helps to keep the right balance of fluids in your body. Your kidneys control how much sodium is in your body. If you have too much and your kidneys can't get rid it, sodium builds up in your blood. This can lead to high blood pressure. High blood pressure can lead to other health problems.

Most people in the U.S. get more sodium in their diets than they need. A key to healthy eating is choosing foods low in sodium. The Dietary Guidelines recommend that most adults eat less than 2.3 grams per day. That equals about 1 teaspoon of table salt a day. Some people are more sensitive to the effects of salt than others and should eat less. This includes people who have high blood pressure, diabetes, or kidney problems, or are African American or over age 50. Reading food labels can help you see how much sodium is in prepared foods.

NIH: National Heart, Lung, and Blood Institute

[Learn More in MedlinePlus]

Code History

• FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
• FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
• FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
• FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
• FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
• FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
• FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
• FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
• FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.