Drug electrophoresis

Medicinal electrophoresis is a combined physical and chemical method of local exposure to direct electric current and medicinal agents introduced by means of current through electrodes and hydrophilic pads moistened with a solution of these agents and contacted with the skin surface or mucous membranes of certain areas of the patient's body.

Current density is 0.05-0.1 mA/cm2, voltage is 30-80 V. The list of drugs for electrophoresis, their percentage content in the solution, as well as the polarity of their introduction are determined by physicochemical studies.

The characteristics of the combined effect and the main clinical effects are determined by the influence of direct current and the corresponding drug.

Electrophoresis involves introducing medicinal substances into tissues in the form of positively and negatively charged particles (ions) through intercellular spaces, ducts of sweat and sebaceous glands. The amount of the introduced medicinal substance is small (2-10% of that contained on the pad) and depends on the properties of the drugs, their concentration, current strength, duration of exposure, area of electrodes, and blood supply to the skin. The bulk of the drugs settles in the epidermis, a small amount - in the dermis and subcutaneous fat. Depositing medicinal substances in the skin provides their long-term reflex or focal effect on the body (for 24 hours or more). Against the background of direct current, the pharmacological activity of drugs increases, since they are introduced into tissues in ionic and chemically pure form. Direct current causes changes in the functional properties of tissues, increasing their sensitivity to medicinal substances. The side effects of drugs are reduced, since they enter the body in small quantities, bypassing the gastrointestinal tract. At the same time, the concentration of the drug in the pathological focus increases and can be several times higher than that achieved with parenteral administration of drugs.

Medicines are introduced into the body according to their polarity: positively charged particles (cations) - from the anode, negatively charged (anions) - from the cathode. The optimal solvent for medicines is distilled water, which provides the best electrolytic dissociation and high electrophoretic mobility of medicines. In addition to water, ethyl alcohol and a universal solvent - dimethyl sulfoxide (dimexide, DMSO), which is also a good carrier of medicines, are used for water-insoluble and poorly soluble substances. 5, 10, 25 and 50% DMSO solutions are used for dissolution.

Complex substances - proteins and amino acids are amphoteric compounds with an isoelectric point. Their electrophoresis is carried out from solutions whose pH differs from the isoelectric point of proteins and amino acids. Acidified (with 5-8 drops of 5% hydrochloric acid) or alkalized (with 5-8 drops of 5% sodium hydroxide) distilled water, as well as buffer solutions (acetate, phosphate buffer, etc.) are used as a solvent for complex substances. Due to the presence of a large number of mobile ions in the buffer solution, its use is limited, therefore, in practice, acidification or alkalization of aqueous solutions is more often used. When acidifying a solution, proteins and amino acids acquire a positive charge and are introduced from the positive pole, when alkalizing - a negative charge and are introduced from the negative pole.

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Indications for drug electrophoresis

Cerebral atherosclerosis, transient ischemic attacks, residual effects and consequences of ischemic and hemorrhagic strokes, condition after removal of vascular aneurysms, cerebral arachnoiditis, consequences of traumatic brain injury, hypothalamic syndromes of various origins, consequences of tick-borne meningoencephalitis, infectious-allergic and traumatic neuritis, neuralgia of the trigeminal, glossopharyngeal, occipital nerves, injuries and diseases of the spinal cord, cervical and lumbar osteochondrosis, Bechterew's disease, vibration disease, Raynaud's disease, etc.

Contraindications to drug electrophoresis

Contraindications are the same as for galvanization, and, in addition, intolerance to drugs.

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Medicinal electrophoresis: mechanism of action

The mechanism of action of medicinal electrophoresis is determined by the influence of galvanic current and the peculiarity of the substance being administered. In the case of using non-potent agents, the main effect is determined by direct current, while in the case of potent agents, the pharmacological properties and specificity of the drug determine the main effect.

Medicinal electrophoresis has an anti-inflammatory, resolving, local anesthetic effect on the body, improves tissue blood supply and conductivity of peripheral nerve fibers, reduces pathological pulsation from the periphery, normalizes the functional state of the central and autonomic nervous system.

Method of medicinal electrophoresis

The method of medicinal electrophoresis does not differ significantly from the method of galvanization. In addition to conventional electrodes, a medicinal pad made of filter paper or several layers of gauze, moistened with a medicinal solution, is used. Medicines can also be administered from solutions through a bath (bath electrophoresis), using the method of intra-tissue electrophoresis. The duration of exposure is 20-30 minutes. The course of treatment is 10-15 procedures, daily or every other day.

The essence of intra-tissue electrophoresis is that the patient is injected with a medicinal substance in one of the known ways (intravenously, subcutaneously, intramuscularly, by inhalation), and then, after reaching its maximum concentration in the blood, galvanization is carried out transversely on the lesion.

Methods of medicinal electrophoresis

In order to increase the efficiency of the method, new methods of medicinal electrophoresis are being developed and existing ones are being improved. In particular, the following methods are proposed for use:

• prolonged galvanization (electrophoresis). Consists of the use of low-power current (100-200 μA) with a long duration of exposure. The technique was developed and introduced into practice by N.A. Gavrikov (1977, 1983). A Krona battery can be used as a source of direct current. The course of treatment is 20-30 procedures. The procedures have a sedative, analgesic, vasoregulatory effect on the body. They are used for long-term, persistent pain syndromes, in the complex therapy of genuine and traumatic epilepsy, and degenerative-dystrophic lesions of the joints and spine;
• labile galvanization or electrophoresis. One of the electrodes (indifferent) is fixed stably, the second moves at a speed of 3-5 cm per second along the body surface. To eliminate current fluctuations during the impact, a stabilizing device is additionally introduced into the apparatus. The procedures promote an increase in metabolic processes, increased blood supply to tissues, improved excitability and conductivity of neuromuscular formations. It is advisable to use the method in combination with the treatment of patients with traumatic neuritis, toxic and primary polyneuropathies and polyradiculoneuritis, neuroses (hysteria), etc.;
• intra-tissue (intra-organ) electrophoresis or electroelimination. A medicinal substance or a mixture of substances is administered intravenously by jet or drip, through a cannula, subcutaneously, or intramuscularly. Galvanic electrodes are applied transversely to the lesion so that the concentration of drugs in the area of the pathological process is increased due to improved blood supply, microcirculation, and increased tissue adsorption capacity. With jet administration of drugs, the galvanic current is turned on simultaneously with the administration of the drug, with drip administration - after the administration of 2/3 of the contents of the dropper, and with parenteral administration - when the maximum concentration of the drug in the blood is reached. With intra-tissue electrophoresis, it is possible to use a mixture of medicinal substances; drugs are administered without regard to polarity; there is no loss of drugs.

In a neurological clinic, intra-tissue electrophoresis can be used for injuries and diseases of the central nervous system;

• vacuum electrophoresis - electrophoresis under reduced atmospheric pressure. The EVAK-1 device is used, consisting of a vacuum pump, vacuum cuvettes, and a Potok-1 galvanization device. Vacuum electrophoresis with rectified currents is carried out on the corresponding devices for low-frequency therapy. The cuvettes are rubber or plastic caps with spring-loaded lead electrodes inside. During the procedure, the cuvette is applied to the skin or mucous membrane, the pad is moistened with a medicinal solution. After creating a discharged pressure, the skin is lifted up and tightly contacts the medicinal pad. The duration of the procedure is 5-10 minutes. It is possible to act on 2-3 areas in turn. Vacuum electrophoresis is carried out once every 4-5 days. The course of treatment is 5-10 procedures. With vacuum electrophoresis, the amount of the administered medicinal substance and the depth of its penetration increase. Vacuum therapy helps to increase metabolism and improve blood circulation. The method can be used for chronic pain syndrome in patients with cervical and lumbar osteochondrosis, and for injuries to peripheral nerves;
• Microelectrophoresis. During the procedure, a cotton pad is used, into the socket of which a cotton wick soaked in a medicinal solution is inserted. An electrode is placed on top of it so as to create contact between the metal tip and the cotton wool. The pad with the wick is placed with the convex side on the acupuncture point (AP). The AP is affected through acupuncture needles made of stainless steel using special clamps. The wires from the clamps are fixed to the skin with adhesive tape to avoid tension and bending of the needles. Microelectrophoresis is carried out by penetrating the medicinal substance into the AP. The current on the face is 5-50 μA, on the body - 100-120, on the limbs 100-200 μA. The duration of exposure is 2-30 minutes. The following devices are used for electropuncture and microelectrophoresis in TA: PEP-1, Elite-1, ELAP type, Reflex-30-01, Indicator-2 MT, Biotonus, etc. Microelectrophoresis is advisable to prescribe for hypertension stage 1-11A, migraine, insomnia, postencephalitic hyperkinesis, diseases of the peripheral nervous system (radiculitis, neuralgia, traumatic neuritis and plexitis, facial nerve neuritis), consequences of traumatic brain injury;
• combined action of ultrasound and electrophoresis - electrophonophoresis of medicinal substances. A special device has been manufactured, consisting of a therapeutic source of high-frequency alternating current, a converting ultrasound sensor, a source of rectified and stabilized current, an electric nozzle, and an indifferent electrode. The electric nozzle consists of two cylinders placed one inside the other. The space between their walls is filled with a medicinal solution. The base of the inner cylinder is the radiating surface of the ultrasound sensor inserted into the cylinder. At the bottom, the space between the cylinder walls is made of Teflon and has 6 round holes filled with porous glass. Above them, in the cavity between the cylinder walls, a ring-shaped metal electrode is installed, which contacts the medicinal substance solution.

The procedure is performed as follows: an indifferent electrode is fixed to the skin and connected to one of the poles of the current source. The electrode attachment filled with the medicinal solution is fixed to the ultrasound sensor and connected to the other pole of the current source. The current is gradually increased to the required value (current density 0.03-0.05 mA/cm2), then the ultrasound is turned on (intensity 0.2-0.6 W/cm2). The zones are affected by stable and labile methods for 10-15 minutes. The course of treatment is 10-15 procedures, daily or every other day.

The method can be used in the treatment of patients with cervical and lumbar osteochondrosis with pain syndrome, neuralgic pain of various origins.

For the introduction of medicinal substances, in addition to galvanic, a pulsating current can be used, constant in direction but periodically changing in voltage, as well as rectified pulsed low-frequency currents (diadynamic, sinusoidal modulated, rectangular, exponential, fluctuating), which have an electrophoretic effect. In this case, the analgesic, vasodilatory, resorptive effect of pulsed currents and administered medicinal substances is potentiated. Compared with classical electrophoresis, with electrophoresis with pulsed currents, a smaller amount of medicinal substances is administered, but the depth of their penetration increases somewhat. Electrophoresis with pulsed currents is used to treat patients with pain and vegetative-vascular syndromes, with spinal cord injuries, neuritis of the facial nerve, etc.