Mepivastezine

Mepivastezine is a local anesthetic from the amide subgroup. The anesthetic effect after its application begins very quickly - due to the temporary suppression of the conduction of neural impulses within sensory, autonomic, as well as motor fibers and conduction inside the heart.

Used in dental procedures. There is a rapid development of the analgesic effect (it takes 1-3 minutes) with a high degree of its intensity, as well as good local tolerance. [1]

Indications Mepivastezine

It is used for conduction and infiltration anesthesia during dental procedures. The medicine is prescribed for simple procedures for removing teeth , preparing a cavity and processing a dental stump before restoration and installation of orthopedic elements.

In particular, Mepivastezine is recommended for persons who cannot use vasoconstrictor substances.

Release form

The release of the therapeutic agent is carried out in the form of an injection liquid - inside 1.7 ml cartridges. The jar contains 50 of these cartridges.

Pharmacodynamics

The effect of the drug develops when the stress-dependent Na channels are blocked inside the walls of the neuronal fiber. The drug enters through the neural wall into the cell as a base, but the mepivacaine cation, which is formed when a proton is reattached, has an active effect. In the case of a low pH (for example, in inflamed areas), only a small part of the drug has a basic form - due to which the analgesic effect can be weakened.

The duration of the therapeutic effect in the case of pulpal anesthesia lasts at least 20-40 minutes; if soft tissue anesthesia is performed, it lasts within 45-90 minutes. [2]

Pharmacokinetics

Mepivastezine is absorbed at high speed and in large volumes. The indicator of protein synthesis is in the range of 60-78%. The half-life is approximately 2 hours.

The level of the distribution volume is 84 liters; clearance indicator - 0.78 l / min.

The substance mepivacaine is involved in intrahepatic metabolic processes; excretion of metabolic elements is realized through the kidneys.

Dosing and administration

The medication is used exclusively as an anesthetic in dentistry. To achieve effective pain relief, it is required to use the minimum effective dose of the drug - for an adult, 1-4 ml of the substance is often enough.

A child over 4 years old with a weight of 20-30 kg is injected with a portion of 0.25-1 ml, and a child with a weight in the range of 30-45 kg - 0.5-2 ml. The amount of medication used is selected taking into account the weight and age of the child, as well as the duration of the procedure. The average serving equals 0.75 mg / kg mepivacaine.

In older people, an increased plasma index of drugs may be noted - due to a low distribution volume and weakened metabolic processes. The likelihood of cumulation of mepivacaine is especially increased in the case of repeated (additional) drug administrations. A similar effect can develop in the case of a weakened patient's condition and with severe renal / hepatic dysfunction. In this case, it is necessary to reduce the portion of the drug (use the minimum volume of the substance, leading to sufficient anesthesia).

The portion sizes of Mepivastezin for persons with certain pathologies (for example, atherosclerosis or angina pectoris) are reduced in the same way.

The maximum allowable adult dosage is 4 mg / kg drug. Thus, a person weighing 70 kg can use no more than 0.3 g of mepivacaine (10 ml of a medicinal solution).

For children over 4 years old, the portion is selected taking into account weight and age, as well as the duration of the procedure being performed. The maximum amount of the administered portion is 3 mg / kg.

The scheme of drug administration.

When injecting drugs, special cartridge syringes are used, which are designed for reusable administration. Before use, the medicinal liquid should be inspected for discoloration and particles, and the container should be inspected for damage. If the presence of such defects has been identified, the cartridge is not used.

It is forbidden to mix injectable liquid with any other medicines inside the same syringe.

In order to prevent the introduction of the substance into the vessel, it is necessary to carefully perform the aspiration test, using at least 2 planes (degree of needle rotation - 180º). It should be borne in mind that a negative result during aspiration does not guarantee the risk of accidental and unnoticed insertion of the needle into the vessel.

The rate of application of the drug should be maximum 0.5 ml over a period of 15 seconds. This corresponds to the introduction of 1 cartridge per minute.

Most of the common manifestations associated with accidental injection into the vessel can be prevented by correctly performing the injection procedure after aspiration - injection of 0.1-0.2 ml of the substance at a low speed, and then the same slow application of the remainder - after at least 20 -30 seconds.

Any liquid left inside the cartridges after the completion of the dental procedure must be disposed of. It is forbidden to use such residues for administration to other patients.

• Application for children

The medication can be used in persons over 4 years of age.

Use Mepivastezine during pregnancy

Clinical tests of the use of mepivacaine hydrochloride during pregnancy have not been performed. Animal tests did not reveal enough information regarding the possible effect of drugs on the course of pregnancy, intrauterine fetal development, the process of childbirth and postpartum development.

The drug crosses the placenta. In comparison with other local anesthetics, the introduction of mepivacaine in the 1st trimester can provoke abnormalities in fetal development. Therefore, at an early stage of gestation, Mepivastezin is prescribed only if other local anesthetics cannot be used.

There is no information about whether the drug can be excreted in mother's milk. If there is a need to use mepivacaine in a breastfeeding woman, breastfeeding is allowed to continue 24 hours after the use of drugs.

Contraindications

The main contraindications:

• severe intolerance caused by the action of the elements of the drug, or allergy to local amide anesthetics;
• hyperthermia, which has a malignant form;
• cardiac conduction disorder (diagnosed bradycardia or AB-blockade of the 2-3rd stage) or AV conduction, in which a pacemaker is not used;
• a strong decrease in blood pressure or AHF indicators;
• epilepsy that cannot be controlled with medication;
• porphyria.

Side effects Mepivastezine

Among the side symptoms associated with the work of the NS: nausea, headaches, suppression or excitement of the activity of the central nervous system, ear noise, nervousness, metal taste and dizziness. In addition, anxiety, drowsiness, restlessness, vomiting, logorrhea and nystagmus are observed. Euphoria, tremors, numbness, fever or coldness, yawning, muscle twitching and disturbance of consciousness are also possible. In addition, diplopia and visual fogging, loss of consciousness, arrest, paralysis or suppression of respiratory processes, convulsions of the tonic-clonic type and a coma are noted.

In the event of the development of such symptoms, it is necessary to lay the patient horizontally, perform oxygen ventilation, and in addition, monitor his condition all the time in order to prevent deterioration, in which convulsions appear with further suppression of the central nervous system function. Signs of arousal are of a short-term nature or do not appear at all - in this case, the first symptom may be drowsiness, which turns into unconsciousness with cessation of breathing. Often, the onset of drowsiness when using mepivacaine is an early manifestation of an increase in the blood count of the drug and develops due to rapid absorption.

Problems affecting the activity of the CVS: tachycardia, arrhythmia, suppression of the CVS function, hypotension, ventricular arrhythmia (fibrillation and extrasystole), bradycardia and cardiac conduction disorders, and besides this, the failure of the CVS, which can cause cardiac arrest. Such signs of suppression of CVS activity are often associated with a vasovagal effect, especially when the patient is standing. Sometimes they arise directly from the influence of the medicine. If it is impossible to recognize prodromal symptoms, including dizziness, changes in pulse, sweat and weakness, a cerebral form of hypoxia (which has a progressive nature), convulsions or severe dysfunction of the CVS may develop. The patient should be laid horizontally, perform oxygen ventilation, and, if necessary, perform intravenous infusion. In the absence of contraindications, vasoconstrictor agents (for example, ephedrine) are used.

Dysfunction of the mediastinal and sternum organs, as well as the respiratory tract: tachypnea or bradypnea, which can cause apnea.

Immune lesions: symptoms of intolerance, including urticaria, anaphylaxis, rashes, anaphylactoid manifestations, fever and Quincke's edema.

If negative symptoms develop, the use of local anesthetic should be discontinued.

Overdose

Signs provoked by the influence of mepivacaine include tinnitus, tachypnea, metal taste, vomiting, dizziness, anxiety, and nausea. In addition, tremors, bradycardia, seizures, drowsiness and paralysis of the respiratory center, as well as seizures, disturbances of consciousness or cardiac conduction, a decrease in blood pressure, spasms of the tonic-clonic type, coma and cardiac arrest may develop.

Negative symptoms, indicating an increased level of local anesthetic inside the blood, appear either immediately (if accidentally injected into the vessel), or when absorption is disturbed (if it is introduced into an inflamed area or an area where many vessels are located).

If negative signs appear, the administration of Mepivastezine should be canceled.

Therapy.

Control over the indicators of pressure and pulse, and besides this, over the consciousness and breathing rate. In addition, it is necessary to maintain and restore respiratory activity and blood flow function, intravenous and oxygen access.

With an increase in blood pressure, you need to keep the upper body in an elevated position. If necessary, nifedipine is administered sublingually.

In case of seizures, the patient should be monitored so that he does not get injured, and, if necessary, diazepam is administered.

If there is a decrease in blood pressure, the patient needs to lie down horizontally. If necessary, saline solutions and vasoconstrictor agents (including epinephrine, as well as IV cortisone) are injected by the intravascular method.

With bradycardia, atropine is administered.

In case of anaphylaxis, you need to call an ambulance, and also lay the patient horizontally, slightly raising his legs. In addition, he is injected with saline solutions and given intravenous injections of cortisone or epinephrine.

For cardiac shock, keep your upper body in an elevated position and seek medical attention.

When the CVS function stops, mechanical ventilation and indirect cardiac massage are performed, and in addition, resuscitation procedures.

Interactions with other drugs

Substances that block the action of Ca channels and adrenergic blockers potentiate the suppression of myocardial contraction and conduction. If the patient needs to administer sedative drugs (to reduce the feeling of fear), the dosage of the anesthetic is reduced, since it also has a suppressive effect on the central nervous system.

When administered together with anticoagulants, the risk of bleeding increases.

In persons using antiarrhythmic substances, after the use of Mepivastezine, there may be a potentiation of side symptoms.

When combined with chloroform, thiopental, central anesthetic and sedative drugs, toxic synergism may occur.

Storage conditions

Mepivastezine must be stored in a place protected from the penetration of small children. Temperature values - no more than 25 ° С.

Shelf life

Mepivastezine can be used within a 5-year term from the date of manufacture of the drug substance.

Analogs

Analogues of drugs are drugs Mepifrin, Versatis and Articaine with Bucaine hyperbar, Omnikaine and Emla with Brilocaine-adrenaline, as well as Ultracaine with Lidocaine hydrochloride.