Mepivastesin

Mepivastezine is a local anesthetic from the amide subgroup. The anesthetic effect after its use begins very quickly - due to the temporary suppression of the conductivity of neural impulses within sensory, vegetative, and motor fibers and conductivity within the heart.

Used in dental procedures. Rapid development of analgesic effect (requires 1-3 minutes) with a high degree of its intensity, as well as good local tolerance are noted. [ 1 ]

Indications Mepivastesin

It is used for conduction and infiltration anesthesia in dental procedures. The medicine is prescribed for simple procedures of tooth extraction, cavity preparation and dental stump treatment before restoration and installation of orthopedic elements.

In particular, Mepivastezin is recommended for individuals who cannot use vasoconstrictor agents.

Release form

The therapeutic agent is released in the form of an injection liquid - inside cartridges with a volume of 1.7 ml. Inside the jar there are 50 such cartridges.

Pharmacodynamics

The drug's effect develops when stress-dependent Na channels are blocked inside the walls of the neuronal fiber. The drug penetrates the neuronal wall into the cell as a base, but the active effect is exerted by the mepivacaine cation, which is formed when the proton is reattached. In the case of a low pH (for example, in inflamed areas), only a small part of the drug has a base type - due to which the analgesic effect may 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

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

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

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

Dosing and administration

The drug is used exclusively as an anesthetic in dentistry. To achieve effective pain relief, it is necessary 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 of age weighing 20-30 kg is given a dose of 0.25-1 ml, and a child weighing 30-45 kg is given 0.5-2 ml. The volume of the drug used is selected taking into account the weight and age of the child, as well as the duration of the procedure. On average, the dose is 0.75 mg/kg of mepivacaine.

Elderly people may have an increased plasma index of the drug due to a low distribution volume and weakened metabolic processes. The probability of mepivacaine accumulation increases especially in the case of repeated (additional) administrations of the drug. A similar effect may develop in the case of a weakened patient and severe renal/hepatic dysfunction. In this case, it is necessary to reduce the dose of the drug (use the minimum volume of the substance that leads to sufficient anesthesia).

The dosage size of Mepivistin for people with certain pathologies (for example, atherosclerosis or angina) is reduced according to the same scheme.

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

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

Scheme of drug administration.

When administering drugs, special syringe cartridges are used, which are intended for repeated administration. Before use, the medicinal liquid must be inspected for discoloration and the presence of particles, and the container - for damage. If such defects are detected, the cartridge is not used.

The injection liquid must not be mixed with any other medications in the same syringe.

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

The rate of application of the drug should be a maximum of 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 intravascular injection can be prevented by performing the injection procedure correctly after aspiration - injecting 0.1-0.2 ml of the substance at a low speed, and then equally slowly applying the remainder - after at least 20-30 seconds.

Any liquid remaining inside the cartridges after the dental procedure is completed must be disposed of. It is prohibited 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 Mepivastesin during pregnancy

Clinical trials of mepivacaine hydrochloride use during pregnancy have not been performed. Animal tests have not revealed sufficient information regarding the possible effects of the drug on the course of pregnancy, intrauterine development of the fetus, the process of labor and postnatal development.

The drug crosses the placenta. Compared to other local anesthetics, the introduction of mepivacaine in the 1st trimester can provoke abnormalities in fetal development. Therefore, in the early stages of gestation, Mepivacaine is prescribed only if other local anesthetics cannot be used.

There is no information on whether the drug can be excreted in breast milk. If mepivacaine needs to be used by a breastfeeding woman, breastfeeding can be continued after 24 hours have passed since the drug was administered.

Contraindications

Main contraindications:

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

Side effects Mepivastesin

Side effects associated with the nervous system include nausea, headaches, CNS depression or stimulation, tinnitus, nervousness, metallic taste, and dizziness. In addition, anxiety, drowsiness, restlessness, vomiting, logorrhea, and nystagmus are observed. Euphoria, tremor, numbness, heat or cold, yawning, muscle twitching, and impaired consciousness are also possible. In addition, diplopia and visual blurring, loss of consciousness, respiratory arrest, paralysis, or suppression of respiratory processes, tonic-clonic seizures, and coma are observed.

If such symptoms develop, the patient should be laid horizontally, oxygen ventilation should be performed, and in addition, his condition should be constantly monitored to prevent deterioration, in which convulsions with further suppression of the central nervous system function appear. Signs of agitation are short-term or do not appear at all - in this case, the first symptom may be drowsiness, which turns into unconsciousness with respiratory arrest. Often, the appearance of drowsiness when using mepivacaine is an early manifestation of an increase in blood levels of the drug and develops due to rapid absorption.

Problems affecting the cardiovascular system: tachycardia, arrhythmia, suppression of cardiovascular function, hypotension, ventricular arrhythmia (fibrillation and extrasystole), bradycardia and cardiac conduction disorders, as well as cardiovascular failure, which can cause cardiac arrest. Such signs of cardiovascular suppression are often associated with the vasovagal effect, especially when the patient is standing. Sometimes they occur directly due to the effect of the drug. If prodromal symptoms such as dizziness, changes in pulse, sweating and weakness cannot be recognized, cerebral hypoxia (progressive), seizures or severe cardiovascular dysfunction may develop. The patient should be placed horizontally, oxygen ventilation should be performed, and intravenous infusions should be administered if necessary. In the absence of contraindications, vasoconstrictor agents (ephedrine) are used.

Disorders of the function of the organs of the mediastinum and sternum, as well as the respiratory tract: tachypnea or bradypnea, which can cause apnea.

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

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

Overdose

Signs caused by the influence of mepivacaine include: tinnitus, tachypnea, metallic taste, vomiting, dizziness, anxiety, and nausea. In addition, tremors, bradycardia, convulsions, drowsiness, and respiratory paralysis may develop, as well as convulsions, impaired consciousness or cardiac conduction, decreased blood pressure, tonic-clonic spasms, coma, and cardiac arrest.

Negative symptoms indicating an increased level of local anesthetic in the blood appear either immediately (in case of accidental injection into a vessel) or in case of absorption disorder (in case of injection into an inflamed area or an area where there are many vessels).

If negative signs appear, Mepivistin administration should be discontinued.

Therapy.

The blood pressure and pulse indicators are monitored, as well as consciousness and respiratory rate. In addition, it is necessary to maintain and restore respiratory activity and blood flow function, intravenous and oxygen access.

If the blood pressure increases, the upper body should be kept in an elevated position. If necessary, nifedipine is administered sublingually.

In case of seizures, the patient must be monitored to ensure that he does not get injured, and diazepam must be administered if necessary.

If the blood pressure level decreases, the patient should lie down horizontally. If necessary, saline solutions and vasoconstrictor agents (including epinephrine and intravenous cortisone) are administered intravascularly.

In case of bradycardia, atropine is administered.

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

In case of cardiac shock, you need to keep your upper body elevated and call for medical help.

When the cardiovascular system stops functioning, artificial ventilation and indirect cardiac massage are performed, as well as 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 it is necessary to administer sedatives to the patient (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 individuals using antiarrhythmic agents, potentiation of side effects may be observed after the use of Mepivistin.

When combined with chloroform, thiopental, central analgesics and sedatives, toxic synergism may occur.

Storage conditions

Mepivastezin should be stored in a place closed to small children. Temperature values are no more than 25°C.

Shelf life

Mepivastesin can be used within a 5-year period from the date of manufacture of the medicinal substance.

Analogues

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