Sweat electrolytes test

Sweat Electrolytes Test (ETT)

A sweat electrolytes test (ETT) is a medical test prescribed by a doctor to evaluate the electrolyte balance in the sweat of an individual. It helps to detect potential disturbances in the functioning of various organs, such as the heart, goive, and kidneys. The test is also used to diagnose conditions including cystic fibrosis and other forms of genetic diseases. In addition, the test helps to determine if an individual has a higher-than-normal risk for dehydration, hyponatremia (low sodium levels), or hypernatremia (high sodium levels).


Before the test, the patient is usually advised to stop taking any medication or supplements several days prior to the test. It is important to inform the doctor about any existing medications so that they can be discontinued to avoid possible complications during the ETT. The patient may also need to avoid exercising for several days prior to the test, and may be advised to avoid eating any food up to 8 hours prior to the test.


The ETT usually takes place in a clinical setting and entails collecting a sample of sweat from the skin. The sample is collected by lightly brushing the skin with an absorbent disc, and then the disc is sent to the lab for analysis. After a period of time, the lab provides the results which will be interpreted by the doctor and discussed with the patient.


The ETT comes in two types: quantitative and qualitative. Quantitative ETT measures the concentration of electrolytes in the sweat, while qualitative ETT evaluates the properties of the sweat itself. Depending on the type of ETT, different equipment or methods may be used to collect and analyze the sweat.


The ETT is a safe test with very few risks. The disc used for collecting the sweat may cause some minor irritation or itching on the skin. In some cases, the test may also lead to temporary redness of the tested spot.

Why ETT is recommended?

ETT is usually recommended when a patient is suffering from chronic fatigue, dehydration, recurrent infections, muscle weakness, and other conditions that can be caused by electrolyte imbalance in the body. Additionally, the ETT is also used to determine the severity of organ dysfunctions and identify potential electrolyte imbalances.

When ETT is done?

ETT is done when the doctor suspects a patient may have an electrolyte imbalance. In some cases, the patient may also be advised to undergo ETT if he/she has signs and symptoms of electrolyte disturbances. Additionally, the ETT is used to help doctors diagnose and manage certain medical conditions, including cystic fibrosis and inherited metabolic diseases.