The antidotes of toxic substances

The antidotes of toxic substances (antidote toxic substances) is a specific means of prevention of injuries and the treatment of the affected poisonous substances. The antidotes agents are available as a means of first aid in all health centres and hospitals, and are equipped units and stages of medical evacuation in the system of medical service of troops and civil defense.
The antidotes of toxic substances include funds detoxification which occur as a result of adsorption and subsequent removal of toxic substances from the body or by chemical neutralization them with the formation of non-toxic (malotoksicen) substances. The mode of action of the antidotes of toxic substances are divided into four groups.
1. The antidotes physico-chemical actions include enveloping and absorbent material. In practice became widespread only the last - activated (wood, animal) coal and white clay. These funds are effective only if the earlier application, prior to absorption of toxic substances in the blood.
2. The chemical antidotes actions neutralize the toxic substances in the blood and tissues of the victim due to neutralization S or education malotoksicen or harmless substances. For example, if poisoning cyanide use of sodium hyposulphite; formed harmless compounds are excreted with the urine. Diphosgene can be neutralized by hexamethylenetetramine (a + ) in the case of the early adoption of the latest, prior to absorption of toxic substances in the tissues and blood of the victim. As a remedy hexamethylenetetramine useless because of the rapid hydrolysis of diphosgene in the body.
3. The antidotes competitive actions directly on toxic substances not work, but come with them in a competitive relationship (antagonism) for the influence of reactive systems of the body. Based on this principle, the use of oxygen as an antidote in case of poisoning with carbon monoxide; thiol compounds with the defeat of lewisite; reaktivatory cholinesterase - drugs group of pyridine (PAM, TMB-4), hydroxylamine with the defeat of poisonous substances such as sarin; atropine and other holinolitikov - with the defeat of poisonous substances nerve.
4. The antidotes physiological actions cause physiological effect opposite to the action of toxic substances. For example, barbiturates appoint sudorozhnom syndrome, caused organophosphorus toxic substances.
As antidotes cyanide compounds used chromosme (methylene blue mixed with glucose). Sometimes apply a few antidotes consistently. So, when cyanide poisoning initially introduced the metgemoglobinoobrazovateley (amyl nitrate), then sulfur-containing substances (Hypo) and glucose; with the defeat of poisonous substances such as sarin - large doses of anticholinergic (atropine) and reaktivatory cholinesterase (PAM), and in severe cases - and narcotic drugs.
Efficiency of antidote therapy depends on the earliest possible start of treatment, use of means and other conditions.
The medical antidotes used after exposure to toxic substances, antidotes prevention for half an hour before you intend contact with poisonous substances. Terms of application of antidotes, the need for re-use, selection of doses and routes of administration shall be determined by their properties, the clinical picture and the degree of gravity of the defeat of poisonous substances, and also the conditions in which it appears medical aid and treatment of the victim (see Chemical weapons).
For many toxic agents (mustard gas, diphosgene)and for BZ (toxic substances that cause temporary, reversible, psychosis) antidotes not found. In such cases, it is nonspecific treatment of the patients.

The antidotes S (from the Greek. antidotos - antidote) - antidote neutralizing toxic substances (S) in the body. In connection with the speed of an intoxication of an organism under the effect of modern ECONOMICAL, often fatal, A. recommended for individual security troops and are facilities in all health centers and institutions rendering first medical aid. The basis of action A. lie patterns characteristic pharmacodynamic antagonism. According to A. this can be divided into the following groups.
1. The antidotes physical actions, such as solvents, which On the skin actions can be removed from the surface of the skin. Some authors refer to this group coals-adsorbents of animal and vegetable origin used in the mist (2-4 table spoon 1/2 l of water) inside the oral defeat S type of mustard gas.
2. The antidotes physiological actions produce the opposite effect On In pharmacological effect, such as substances - by paralyzing poisons (analeptiki - drug poisoning, including methyl alcohol), barbiturates - sudorozhnom syndrome caused by organophosphorus S.
3. The chemical antidotes actions can be divided into subgroups:
a) Antidotes, acting through the formation of water-insoluble compounds, for example Antidotum metallorum - stable solution of hydrogen sulfide, intended for removal from the stomach of salts of heavy metals and metalloids as arsenic, antimony in the form of water-insoluble sulfur compounds;
b) Antidotes, acting by oxidation, such as aqueous solutions of potassium permanganate, used for washing stomach oral mustard gas poisoning, morphine, phosphorus (formed accordingly sulfoxide, oxidisation and phosphoric acid);
in) A. acting through restoration, such as rongalit, or formaldehydesupport sodium, which oral administration in solution 1 : 10 besieging toxic metals such as mercury from various salts;
g) A. competitive actions that seem to deny themselves all the poison that kills normal substrate. This is how, for example, unithiol on arsenic;
d) A. forming complexes with toxic compounds. These include A. lesneven links - the so-called chelation, or chelating agents, such as derivatives ethylenediaminetetraacetic acid (EDTA), calcium-disodium salt which is applied in the form of injections or tablets with poisoning salts of heavy metals type of lead and rare earth metals;
e) A. reactivating enzymes are blocked (inhibited) various poisons. Such, for example, reaktivatory restoring inhibited organophosphate poisons acetyl-cholinesterase [2 PAM - pyridine-2-al-doxil-methodic, TMB-4 - 1,3 bis-(N-pyridine-4-aldoxime)-preponderated].
There are A. General and specific actions. In the first case A. can serve as an antidote group of compounds of similar properties. For example, antidotum metallorum is the antidote of some heavy metals, A. type of unithiol give a positive effect in respect of elimination of a number of salts of mercury, cadmium, cobalt. A. specific actions (for example, reaktivatory cholinesterase) are antidotes strictly selective action.
A. can be direct and indirect action. For example, glucose relative to hydrocyanic acid is A. direct action, it is directly influencing on it, forming cyanhydrin. A. type of sodium nitrite is used in the defeat of cyanide, are A. indirect action: under their influence form methemoglobin, which connects hydrocyanic acid, becoming canmet-hemoglobin.
A. therapeutic use after exposure S, A. preventive used for half an hour before you intend contact with the RC. Modern researchers aim to create combined A. (for example, a combination holinoliticakih with reaktivatory in A. organophosphorus S).
Dose various A. - see Poisoning.