Potassium chloride is a potassium salt that is contained in isotonic drinks and some medical products, among other things. In addition, it is one of the components of electrolyte infusion and is indicated for ventricular fibrillation, for example.
What is potassium chloride?
Potassium chloride is used in isotonic drinks and solutions to support electrolyte balance. Potassium chloride (KCl) is the potassium salt of hydrochloric acid. As E508, the mineral is approved in the EU as an additive for food; industry uses it primarily as a flavor enhancer and firming agent. In medicine, the terms potassium chloratum or chlorinated potassium are also commonly used. Potassium chloride is colorless and odorless and dissolves well in water. Therefore, it also functions as an electrolyte in the human body and as such is involved in homeostasis. In its pure form, the substance exists in a solid aggregate state and forms cubic crystals. A potassium chloride molecule consists of a positively charged potassium particle and a negatively charged chloride particle. Potassium chloride is not only used in medicine and the food industry: In agriculture, for example, it can be found as a fertilizer.
Pharmacological action
Potassium chloride is used in isotonic drinks and solutions to support electrolyte balance. In a healthy adult, the blood contains about 300 mosmol of inorganic electrolytes per liter, including potassium. Most osmotic substances in the organism are electrolytes. A deficiency of electrolytes disturbs the electrical balance as well as the water-electrolyte balance of the human body. In this regard, potassium chloride contributes to homeostasis along with other electrolytes, glucose, urea and other substances. Potassium plays an important role in the function of nerve and other cells. Potassium ions are positively charged and thus contribute to the electrical balance of cells. Osmotic pressure causes ions to flow into or out of the cell along the electrical charge gradient. For example, if the cell is negatively polarized, positively charged potassium ions and other particles automatically push inside. In doing so, they must pass through the cell membrane, which consists of a double lipid layer. The cell membrane contains not only ion channels through which the ions can migrate, but also pumps. The ion pumps transport charged atoms from one side of the membrane to the other. Biochemical signaling substances determine whether the ion pumps are active or not – and how well the membrane is permeable to certain ions.
Medical application and use
Medicine uses potassium chloride for potassium deficiency to replenish the body’s potassium stores. Intracardiac administration may be necessary for cardiac fibrillation. However, this decision is up to the treating physician. As with any medication, it depends on the individual case whether the supply of potassium chloride is useful or can even cause harm. Ventricular fibrillation is a specific type of cardiac arrhythmia. Ventricular fibrillation is characterized by rapid ventricular contractions of the heart. The contractions follow each other regularly, with a frequency of about 250 per minute. The ECG makes these abnormalities visible. Physicians usually administer potassium chloride intravenously to treat electrolyte disturbances when the concentration falls below a critical level. Rapid treatment is of great importance, as potassium deficiency can lead to cardiac arrest. Administration via a central venous catheter may be necessary. A central venous catheter is a thin tube that enters one of the body’s major veins at the collarbone. The tube extends to the front of the right ventricle. Ringer’s solution, which can be used by infusion to balance fluid levels, also contains potassium chloride and other electrolytes. The mixture is designed to ensure that blood volume is not increased at the expense of water-electrolyte balance. Furthermore, some toothpastes contain potassium chloride. These special pastes are used not only to clean teeth, but also to relieve pain. The toothpastes are designed to reduce pain signals caused by irritation of the gums and teeth during brushing. Dentists often recommend such products to people who have very pain-sensitive teeth.Among other things, the special toothpaste is intended to prevent sufferers from stopping brushing their teeth because they find it too painful. Homeopathy also uses preparations based on potassium chloride. The mineral is contained, among other things, in the Schüßler salt No. 4 in a highly diluted concentration.
Risks and side effects
Potassium chloride can be highly toxic in very high doses, especially when injected directly. An overdose potentially causes cardiac arrest. Because of this property, veterinarians use the salt to euthanize animals. The lethal injection used to execute people in some countries also contains potassium chloride. The right dose is therefore essential. The amounts found in food are considered safe. However, not every excess of potassium chloride in the body leads to death. Characteristic signs of hyperkalemia include ringing in the ears, numbness, and confusion. In addition, hallucinations, paresthesias, muscle weakness and tremors may occur. Cardiac disturbances manifest themselves in various ways: The pulse may slow and beat irregularly. Hyperkalemia need not be the result of a potassium chloride overdose, but may also be due to massive hemolysis, renal failure, or adynamia episodica hereditaria. Medicine speaks of hyperkalemia when the potassium content in the blood serum exceeds 5.0 mval per liter. However, myeloproliferative diseases can falsify the measured value. In the case of such an incorrect measurement, doctors speak of pseudohyperkalemia. The cause may be, for example, an increase in platelets. In such cases, plasma is therefore more suitable as a test substance than serum.
