Strophantine is a cardiac glycoside extracted from African trees, shrubs, and climbing plants. The substance interferes with the sodium–potassium balance of cells. This effect has been used by medicine to achieve an increase in the contractility of the heart muscle.
What is strophantine?
Strophantine is used to achieve an increase in the contractile force of the heart muscle. The cardioactive effect of strophantine became known to European physicians as early as 1859 as a participant in Livingston’s expedition to West Africa. At that time, natives used an extract of strophantine seeds as an arrow poison. An explorer accidentally ingested the seed of a liana species belonging to the dog poison family (Apocynaceae) and noticed in himself its effectiveness on the heart. In the course of time, the ingredient strophantine has been found in various members of the dog poison family. There are both trees and bushes, but also lianas climbing in height, which belong to the Strophantus species. For example, Strophantus eminii, Strophantus gratus, Strophantus hispidus and Strophantus kombé are among the suppliers of the natural cardiac glycoside. The plants may contain different species of strophantine. Thus, in medicine, a distinction is made between k-strophantin from the plant species Strophantus kombé, g-strophantin from Strophantus gratus, e-strophantin from Strophantus eminii, and h-strophantin from Strophantus hispidus. For medicinal purposes, mainly the g-strophantine is used. In high doses, the toxic substance has a lethal effect. The Scottish physician Thomas Richard Fraser isolated k-strophantine in 1862. In 1888, the Frenchman Arnaud extracted g-strophantine from the African ouabaio tree. Numerous tinctures with different concentrations of the cardiac glycoside strophantus were offered. The therapeutic effect was initially uncertain, although treatment was given in clinics. Albert Fraenkel, a country doctor from Badenweiler, in addition to his practice at the Pharmacological Institute at the University of Heidelberg and at the University Hospital in Strasbourg, researched substances that he hoped would benefit his patients as cardiac medications. He found that intravenous administration of strophantine produced a good therapeutic effect in heart disease. In order to achieve the desired effect and not endanger patients by administering strophantine, standardized solutions for intravenous administration were developed. Strophantine was considered a standard drug for all types of heart failure until the 1970s. It is used for abnormalities of the heartbeat, weakening or damage to the heart muscle after myocardial infarction, influenza illness or inflammation of the heart muscle in diphtheria, angina pectoris and elevated blood pressure.
Pharmacological action
The pharmacological action of strophantine is the influence of the cardiac glycoside on the sodium–potassium pump. This is a protein-based transport system found in cell membranes. This protein (protein) keeps the flow of sodium ions out of the cell and potassium ions into the cell in balance. The proper functioning of the sodium-potassium pump plays a vital role for heart muscle cells and for nerve cells. In cardiac insufficiencies, imbalances in ion exchange can occur. This has a debilitating effect on the functionality of the heart cells. Intravenous administration of strophantine slows the transport of potassium ions out of the cell. At the same time, the calcium content in the cell is increased. These conditions increase the contractility of the heart muscle cells. A higher dose inhibits the sodium-potassium pump. In contrast, low oral administration of strophantine stimulates ion exchange.
Medical application and use
Strophantine is the cardiac glycoside with the most rapid onset of action of all available cardiac glycosides. Until 1992, strophantine was mentioned in official textbooks as the standard therapy for acute heart failure. Ampoules containing the cardiac glycoside were available in the suitcase of every emergency physician. In the following years and up to the present day, strophantine has hardly been used in the therapy of cardiac diseases in favor of other cardioactive substances such as digoxin, a chemical compound of foxglove (Digitalis purpurea).In the meantime, only outdated studies are available that no longer meet today’s scientific requirements, although the efficacy of strophantine has been proven and documented in a long history of research. In university medicine, the cardiac glycoside strophantine is hardly used anymore. In alternative medicine, however, there are still homeopathic preparations that are used for the relief of chronic diseases of the heart. The pharmacopoeia recommends Strophantus, for example, for mitral valve insufficiency, which is very often accompanied by edema. Strophantus not only stimulates the heart muscles, it also helps to drain the tissues.
Risks and side effects
There are few side effects to worry about when taking or intravenously administering a standardized solution of Strophantus. For many decades, strophantine was considered the cardiac drug that was well effective and best tolerated. Only a mild laxative effect was observed in some cases. Even with a homeopathically potentized drug, no adverse effects are expected if the strophantine was prescribed according to the patient’s individual symptoms. High doses taken in an uncontrolled manner, on the other hand, can have life-threatening effects.