Plants and their products have been used to treat various diseases since the beginning of human civilization. In addition to medical use, the use of toxic compounds is also widespread. Often the same compounds have both dosage-dependent effects. Alkaloids are natural organic compounds, secondary metabolites of living organisms with a pronounced pharmacological effect. Aconitine is one of the most toxic alkaloids. Aconitine and mesaconitine bind with high affinity to sodium channels and cause their constant activation. There is a constant depolarization of the membrane, slowing down heart rate and paralysing the respiratory muscles. Taxin has the greatest impact on the cardiovascular system, leading to disturbances in the conduction of cardiac stimuli due to interference with the ion channels of the heart muscle. It reduces the rate of depolarization of the action potential, which creates bradycardia, conduction delay, arrhythmia, etc. Cardiac glycosides bind to and inhibit Na + / K + -ATPase, leading to an increase in calcium ion concentration and an increase in cardiac contraction strength. Depending on the structure, they are divided into cardenolides and bufadienolides. The action of these compounds is unknown to the general public, which can lead to serious consequences in the form of poisoning.