Lidokain Aguettant: Uses, Dosage & Side Effects

What Is Lidokain Aguettant and What Is It Used For?

Lidokain Aguettant contains the active substance lidocaine hydrochloride, a synthetic amide-type local anesthetic that has been in clinical use since 1948. Lidocaine was first synthesized by the Swedish chemists Nils Löfgren and Bengt Lundqvist in 1943 and represented a revolutionary advancement over the previously available ester-type local anesthetics (such as procaine and cocaine), which were associated with higher rates of allergic reactions and shorter durations of action. Since its introduction, lidocaine has become the most commonly used local anesthetic in the world, serving as the benchmark against which all newer local anesthetics are compared.

Lidocaine belongs to the amide class of local anesthetics, which are characterized by an amide bond linking the aromatic ring to the intermediate chain. This chemical structure confers several important clinical properties: amide local anesthetics are metabolized in the liver (rather than by plasma esterases like ester-type anesthetics), they are remarkably stable in solution, and they carry an extremely low risk of true allergic reactions. The amide group includes other well-known local anesthetics such as bupivacaine, ropivacaine, mepivacaine, and prilocaine, but lidocaine remains the most versatile and widely used member of this pharmacological family.

The mechanism of action of lidocaine involves reversible blockade of voltage-gated sodium channels in neuronal cell membranes. Under normal physiological conditions, the generation and propagation of nerve impulses (action potentials) depends on the rapid influx of sodium ions through these channels. When lidocaine molecules diffuse through the nerve sheath and cell membrane and reach the intracellular side of the sodium channel, they bind to specific receptor sites within the channel pore in its open or inactivated state. This binding prevents sodium ions from flowing through the channel, thereby inhibiting the depolarization phase of the action potential. Without depolarization, nerve impulses cannot be generated or conducted, and the area supplied by the blocked nerve fibers loses sensation.

An important pharmacological feature of lidocaine is its differential nerve block, meaning that not all nerve fibers are blocked equally or simultaneously. Small-diameter, myelinated (A-delta) and unmyelinated (C) fibers that carry pain and temperature signals are typically blocked before larger-diameter motor (A-alpha) and touch (A-beta) fibers. This differential sensitivity means that a patient may lose pain sensation before losing proprioception or motor function. The clinical significance of this phenomenon is that, at appropriate concentrations, lidocaine can provide adequate analgesia (pain relief) while partially preserving motor function, which is desirable in many clinical settings.

Lidokain Aguettant at a concentration of 20 mg/ml (2%) is formulated specifically for injection and is indicated for a broad range of local and regional anesthetic techniques, including:

• Infiltration anesthesia: Direct injection into the tissue surrounding the operative site to numb a small, localized area. This is the most common use of lidocaine and is employed for minor surgical procedures such as wound repair (suturing), skin biopsies, mole removal, abscess drainage, and insertion of intravenous catheters or chest drains.
• Peripheral nerve blocks: Injection of lidocaine around specific nerves or nerve plexuses to anesthetize entire regions of the body. Examples include digital nerve blocks (for finger or toe procedures), intercostal nerve blocks (for rib fracture pain), brachial plexus blocks (for upper extremity surgery), and femoral or sciatic nerve blocks (for lower extremity procedures).
• Epidural anesthesia: Injection into the epidural space of the spinal canal to provide anesthesia to the lower body. Lidocaine 2% can be used for epidural anesthesia in surgical procedures, though longer-acting agents like bupivacaine or ropivacaine are often preferred for prolonged procedures and obstetric epidurals.
• Caudal anesthesia: A form of epidural anesthesia administered through the sacral hiatus, commonly used in pediatric surgery for procedures below the umbilicus.
• Dental anesthesia: Lidocaine is the most widely used local anesthetic in dentistry, providing effective pain control for dental procedures including fillings, extractions, root canals, and periodontal surgery.
• Diagnostic and therapeutic nerve blocks: Used in pain medicine to diagnose the source of pain by selectively blocking specific nerves, or to provide therapeutic pain relief in chronic pain conditions.

The clinical profile of lidocaine as an injectable local anesthetic is characterized by its rapid onset of action (typically 1–5 minutes depending on the injection technique and site), intermediate duration of effect (30 minutes to 2 hours without epinephrine, up to 3 hours with epinephrine), and a well-established safety record spanning more than seven decades of worldwide clinical use. Its recognition by the World Health Organization (WHO) on the Model List of Essential Medicines underscores its fundamental importance to healthcare systems globally and its proven track record of safety and efficacy when used within recommended dosing guidelines.

What Should You Know Before Taking Lidokain Aguettant?

Contraindications

Lidokain Aguettant must not be used in patients who have a known hypersensitivity (allergy) to lidocaine hydrochloride, other amide-type local anesthetics (such as bupivacaine, mepivacaine, prilocaine, or ropivacaine), or any of the excipients in the formulation. True allergic reactions to amide local anesthetics are extremely rare (estimated at less than 1% of all reported adverse reactions to local anesthetics) but can occur. Most reported “allergic reactions” to local anesthetics are actually due to preservatives (such as methylparaben), vasovagal syncope, systemic toxicity from accidental intravascular injection, or anxiety-related symptoms.

Lidocaine injection is also contraindicated in patients with severe hypotension (very low blood pressure), severe forms of heart block (second-degree Mobitz type II or third-degree atrioventricular block) unless a pacemaker is in place, and in patients with decompensated heart failure. The drug should not be injected into inflamed or infected tissue, as the acidic pH of infected tissue reduces the effectiveness of lidocaine by impeding its diffusion through cell membranes.

Specific contraindications apply based on the route of administration. For example, epidural or spinal administration of lidocaine is contraindicated in patients with severe spinal deformity, active central nervous system disease (such as meningitis or tumors), septicemia, coagulopathy or patients on anticoagulant therapy (due to the risk of epidural hematoma), and in the presence of raised intracranial pressure.

Warnings and Precautions

Before administering Lidokain Aguettant, the healthcare professional should consider the following precautions:

• Hepatic impairment: Lidocaine is primarily metabolized in the liver by cytochrome P450 enzymes (CYP1A2 and CYP3A4). Patients with severe liver disease (e.g., cirrhosis, acute hepatitis) have significantly reduced clearance of lidocaine, leading to prolonged elimination half-life and increased risk of systemic accumulation and toxicity. Dose reduction is required in these patients.
• Heart failure: Patients with congestive heart failure have reduced hepatic blood flow, which impairs lidocaine metabolism. Additionally, lidocaine has mild negative inotropic effects at higher plasma concentrations. Dose reduction and careful monitoring are essential in these patients.
• Cardiac conduction abnormalities: Lidocaine should be used with caution in patients with incomplete heart block, bradycardia, or other conduction disturbances, as it may worsen these conditions. Continuous ECG monitoring is recommended when large doses are administered.
• Epilepsy: Local anesthetics, including lidocaine, can lower the seizure threshold. Patients with epilepsy or a history of seizures are at increased risk and require careful dose titration.
• Hypovolemia and shock: Patients with reduced blood volume or in shock are more susceptible to the cardiovascular depressant effects of lidocaine. Volume resuscitation should be performed before or during lidocaine administration in these patients.
• Elderly patients: Age-related decreases in hepatic blood flow, reduced plasma protein binding, and diminished cardiac output may result in higher peak plasma concentrations and prolonged elimination in elderly patients. Dose reduction is generally recommended.
• Debilitated patients: Patients who are acutely ill, cachectic, or debilitated may be more susceptible to the systemic effects of lidocaine and require reduced doses.

Aspiration before injection is critical to avoid accidental intravascular injection. Even with careful aspiration, intravascular injection can occur; therefore, continuous monitoring for signs of systemic toxicity is essential during and after injection. When large total doses are used (e.g., for major nerve blocks or epidural anesthesia), incremental injection with frequent aspiration is recommended rather than rapid bolus administration.

Pregnancy and Breastfeeding

Lidocaine crosses the placenta by passive diffusion and can reach the fetal circulation. However, lidocaine has been used extensively during pregnancy and labor for decades and is generally considered safe when used at recommended doses. It is one of the most commonly used local anesthetics for epidural analgesia during labor and delivery. The American College of Obstetricians and Gynecologists (ACOG) and international guidelines support the use of lidocaine-based epidural analgesia during labor as a safe and effective method of pain management.

During pregnancy, lidocaine should be used only when the potential benefit justifies the potential risk to the fetus, as is the standard recommendation for any medication during pregnancy. High doses or paracervical block with lidocaine during the first stage of labor have been associated with fetal bradycardia, and this technique requires careful monitoring. When lidocaine is used for epidural anesthesia during labor, fetal heart rate monitoring is standard practice.

Lidocaine is excreted in human breast milk in small amounts. The amount transferred to the infant through breastfeeding following local or regional anesthesia is considered negligible and is generally regarded as compatible with breastfeeding. The American Academy of Pediatrics has classified lidocaine as compatible with breastfeeding. Women can typically resume breastfeeding soon after receiving lidocaine for local or regional anesthesia without the need for a waiting period or discarding milk.

Children

Lidocaine can be used in pediatric patients for local and regional anesthesia, but careful weight-based dose calculation is essential. Children, particularly neonates and infants, have immature hepatic enzyme systems and higher proportions of body water, which affect lidocaine distribution and metabolism. The maximum dose for children is 4.5 mg/kg without epinephrine. Specialized pediatric dosing charts should be used, and the total dose must be calculated precisely to avoid the risk of systemic toxicity. Caudal anesthesia using lidocaine is well-established in pediatric surgical practice for lower abdominal and lower extremity procedures.

Driving and Operating Machinery

Depending on the dose, site of injection, and extent of nerve block, lidocaine may temporarily impair motor function, sensation, and coordination in the affected area. Patients should not drive or operate machinery until full sensation and motor function have returned after local or regional anesthesia. This is particularly relevant after dental procedures (risk of biting the tongue or cheek), upper extremity nerve blocks (impaired hand function), or lower extremity blocks (impaired balance and leg strength).

How Does Lidokain Aguettant Interact with Other Drugs?

Lidocaine is metabolized in the liver primarily by the cytochrome P450 enzymes CYP1A2 and CYP3A4. Drugs that inhibit or induce these enzymes can significantly affect lidocaine plasma concentrations and, consequently, the risk of systemic toxicity. Additionally, the pharmacodynamic properties of lidocaine (sodium channel blockade, cardiovascular effects) can interact with other drugs that affect cardiac conduction, heart rate, or blood pressure.

Understanding lidocaine drug interactions is particularly important because the therapeutic window for lidocaine is relatively narrow: therapeutic plasma concentrations for local anesthetic effect are 1.5–5 µg/ml, while toxic effects may begin to appear at concentrations above 5 µg/ml. Any interaction that increases lidocaine plasma levels can shift the concentration toward the toxic range.

Major Interactions

The most clinically significant interactions with lidocaine involve drugs that substantially increase its plasma concentration or produce additive cardiac depressant effects. Fluvoxamine, a selective serotonin reuptake inhibitor (SSRI) and potent CYP1A2 inhibitor, has been shown in pharmacokinetic studies to increase lidocaine plasma concentrations by approximately 70%, which can push levels into the toxic range even with standard doses. Patients taking fluvoxamine who require lidocaine should receive substantially reduced doses with careful monitoring.

Amiodarone, a widely used antiarrhythmic drug, represents a particularly dangerous combination with lidocaine. Both drugs affect cardiac sodium channels, and amiodarone also inhibits the hepatic enzymes that metabolize lidocaine. The combination can result in severe bradycardia, atrioventricular block, or even cardiac arrest. This combination should be avoided whenever possible, and when unavoidable, should be used only under continuous cardiac monitoring with reduced lidocaine doses.

Propranolol and other non-selective beta-blockers reduce hepatic blood flow (the primary site of lidocaine metabolism) and can also directly inhibit CYP2D6, contributing to a 30–40% reduction in lidocaine clearance. This interaction is particularly relevant in patients receiving intravenous lidocaine infusions but can also be clinically significant with large doses of injectable lidocaine for regional anesthesia.

Minor Interactions

Epinephrine (adrenaline), when added to lidocaine solutions, is not an adverse interaction but rather a deliberate clinical strategy. Epinephrine causes local vasoconstriction at the injection site, which slows systemic absorption of lidocaine, prolongs the duration of anesthesia, reduces peak plasma concentrations, and decreases surgical site bleeding. The typical concentration of epinephrine added to lidocaine is 1:200,000 (5 µg/ml). However, epinephrine-containing solutions should be used with caution in patients with severe cardiovascular disease, uncontrolled hypertension, thyrotoxicosis, and in areas supplied by end-arteries (fingers, toes, nose, ears, penis) where vasoconstriction could cause tissue ischemia.

Opioid analgesics, benzodiazepines, and other central nervous system depressants do not have direct pharmacokinetic interactions with lidocaine but may mask early CNS symptoms of lidocaine toxicity (such as dizziness and tinnitus), potentially delaying detection of an emerging toxic reaction. Healthcare professionals should maintain a high index of suspicion for LAST when administering lidocaine to sedated patients.

What Is the Correct Dosage of Lidokain Aguettant?

Unlike oral medications with standardized fixed doses, the dosing of lidocaine for local and regional anesthesia is highly individualized. The appropriate dose depends on numerous factors, including the specific procedure being performed, the area and technique of administration, the vascularity of the tissue at the injection site, the degree of anesthesia required, the patient’s body weight, physical condition, age, and any concurrent medications. The healthcare professional administering the drug must select the dose based on clinical judgment, using the minimum dose necessary to achieve the desired level of anesthesia.

Adults

The maximum recommended dose of lidocaine without epinephrine in adults is 4.5 mg/kg body weight, not exceeding a total of 300 mg per administration session. When epinephrine (adrenaline) is co-administered, the maximum dose may be increased to 7 mg/kg, not exceeding a total of 500 mg, because epinephrine reduces the rate of systemic absorption and lowers peak plasma concentrations. These maximum dose limits should not be exceeded under any circumstances, as doing so significantly increases the risk of local anesthetic systemic toxicity (LAST).

For a 70 kg adult, the maximum dose without epinephrine would be 315 mg (4.5 mg/kg × 70 kg), capped at the 300 mg absolute maximum. This corresponds to 15 ml of the 2% (20 mg/ml) solution. With epinephrine, the maximum would be 490 mg (7 mg/kg × 70 kg), corresponding to approximately 24.5 ml of the 2% solution.

Children

In pediatric patients, the maximum dose of lidocaine without epinephrine is 4.5 mg/kg body weight. Weight-based dose calculation is mandatory for all children, and the total dose must never be estimated — it should be calculated precisely using the child’s actual weight. Neonates and infants under 6 months have immature hepatic enzyme systems, resulting in prolonged elimination half-life and increased susceptibility to toxicity. In this age group, doses should be further reduced and the interval between repeat doses extended.

For caudal anesthesia in children, the dose of lidocaine 2% is typically calculated based on the desired level of block: approximately 0.5 ml/kg provides sacral block (perineal procedures), 1.0 ml/kg provides lower thoracic block (lower abdominal procedures), and 1.25 ml/kg provides mid-thoracic block. These volumes must be verified to ensure the total lidocaine dose does not exceed the 4.5 mg/kg maximum.

Elderly Patients

Elderly patients often require reduced doses of lidocaine due to age-related physiological changes including decreased hepatic blood flow, reduced hepatic enzyme activity, decreased cardiac output, increased body fat percentage (affecting distribution), and reduced plasma protein binding. The dose should be reduced by approximately 20–30% in elderly patients compared to younger adults. For epidural anesthesia, the dose per segment may also need to be reduced, as age-related changes in the epidural space (reduced volume, increased permeability) may result in more extensive spread of the anesthetic solution.

Missed Dose

Lidokain Aguettant is not a medication that is taken on a regular schedule. It is administered as needed for specific procedures by healthcare professionals. There is no concept of a “missed dose” for this medication. If a procedure is postponed, the lidocaine will simply be administered at the rescheduled time.

Overdose

Lidocaine overdose (or local anesthetic systemic toxicity, LAST) occurs when plasma lidocaine concentrations exceed the toxic threshold, which typically begins at approximately 5 µg/ml. This can result from accidental intravascular injection, administration of excessive total doses, or rapid absorption from highly vascular injection sites. The presentation of LAST is classically described as a biphasic pattern, progressing from central nervous system (CNS) excitation to CNS depression, and then to cardiovascular collapse.

Early CNS symptoms of lidocaine toxicity include circumoral numbness (tingling around the lips and tongue), metallic taste, tinnitus (ringing in the ears), dizziness, lightheadedness, visual disturbances (blurred vision, diplopia), slurred speech, and muscle twitching. As plasma concentrations increase further, generalized tonic-clonic seizures may occur. At very high concentrations, CNS depression supervenes, leading to loss of consciousness and respiratory arrest.

Cardiovascular toxicity typically manifests at higher plasma concentrations than CNS toxicity. Initial signs may include hypertension and tachycardia (due to CNS excitation), followed by progressive hypotension, bradycardia, conduction abnormalities (widened QRS complex, prolonged PR interval), ventricular arrhythmias, and ultimately cardiovascular collapse and cardiac arrest. In some cases, particularly with rapid intravascular injection, cardiovascular collapse may occur simultaneously with or even before CNS symptoms.

What Are the Side Effects of Lidokain Aguettant?

The side effects of lidocaine can be divided into two broad categories: local effects at the injection site and systemic effects resulting from absorption of lidocaine into the bloodstream. The majority of adverse reactions to lidocaine are dose-dependent and predictable based on its pharmacological mechanism of action. True adverse drug reactions (idiosyncratic or allergic) are exceptionally rare with amide-type local anesthetics.

It is important to distinguish between the expected pharmacological effects of lidocaine (numbness, temporary motor weakness in the anesthetized area) and true adverse effects. Additionally, many symptoms reported during local anesthesia (anxiety, palpitations, sweating, pallor, nausea) are actually related to the injection procedure itself, anxiety, vasovagal response, or the effects of co-administered epinephrine rather than lidocaine toxicity.

The risk of systemic side effects is directly related to the plasma concentration of lidocaine. At therapeutic concentrations used for local anesthesia (1.5–5 µg/ml), systemic effects are minimal. As concentrations rise above 5 µg/ml, CNS symptoms begin to appear. At concentrations above 8–10 µg/ml, serious CNS toxicity (seizures, loss of consciousness) is likely. Cardiovascular toxicity typically occurs at even higher concentrations, although in some cases cardiovascular collapse may be the presenting feature of LAST, particularly with rapid intravascular injection.

If you are undergoing a procedure with lidocaine and experience any unusual symptoms such as ringing in the ears, metallic taste, dizziness, numbness around your lips, or visual changes, inform your healthcare provider immediately, as these may be early warning signs of systemic toxicity that can be managed if detected promptly.

How Should You Store Lidokain Aguettant?

Lidokain Aguettant solution for injection should be stored at controlled room temperature, not exceeding 25°C (77°F). The product should be stored in its original packaging to protect it from light. Do not freeze the solution, as freezing may alter the physical and chemical properties of the formulation. As a sterile injectable product, storage conditions are critical to maintaining the safety and efficacy of the medication.

Do not use Lidokain Aguettant after the expiry date printed on the label and outer packaging. The expiry date refers to the last day of that month. After expiration, the chemical stability and sterility of the product can no longer be guaranteed, and using expired medication could result in reduced efficacy or potential harm.

Lidokain Aguettant is a preservative-free, single-use product. Each container is intended for a single administration session. Once the container has been opened, any solution not used immediately should be discarded. The product should not be re-sterilized or stored for later use after opening. This is because once the seal is broken, the sterility of the solution can no longer be ensured, and microbial contamination could lead to serious infections if contaminated solution is injected.

Before use, visually inspect the solution. It should be clear, colorless to slightly yellowish, and free from visible particles. Do not use the solution if it appears cloudy, discolored, or contains particulate matter, or if the container appears damaged or has been previously opened. The pH of the solution is typically between 5.0 and 7.0, which is necessary for chemical stability and clinical effectiveness.

Keep this medicine out of the sight and reach of children. In hospital and clinic settings, Lidokain Aguettant should be stored in a secure medication area in accordance with local institutional policies for controlled or prescription medications. Do not dispose of medicines via wastewater or household waste; follow local guidelines for the disposal of pharmaceutical waste to help protect the environment.

What Does Lidokain Aguettant Contain?

Each milliliter of Lidokain Aguettant solution for injection contains 20 mg of lidocaine hydrochloride as the active ingredient. This corresponds to a 2% weight/volume (w/v) concentration, which is one of the standard concentrations used worldwide for injectable local anesthesia. Lidocaine hydrochloride is the water-soluble salt form of lidocaine, formed by combining the free base with hydrochloric acid. The hydrochloride salt is used because it provides adequate water solubility for formulation as an injectable solution and is stable in aqueous solution.

The other ingredients (excipients) in Lidokain Aguettant serve specific pharmaceutical functions:

• Sodium chloride: Added to adjust the tonicity (osmolality) of the solution to make it isotonic with body fluids. An isotonic solution reduces pain on injection and minimizes tissue irritation. The concentration of sodium chloride is carefully calculated to achieve an osmolality close to that of plasma (approximately 280–300 mOsm/kg).
• Sodium hydroxide and/or hydrochloric acid: Used for pH adjustment. The solution is buffered to a pH range of approximately 5.0–7.0. This slightly acidic pH is necessary for chemical stability of lidocaine in solution and ensures that the drug remains in its ionized (water-soluble) form during storage. After injection, the tissue buffering capacity raises the pH to physiological levels, converting a portion of the lidocaine to its un-ionized free base form, which is the form that can penetrate nerve cell membranes and reach the intracellular binding site on sodium channels.
• Water for injections: Purified, sterile water that serves as the solvent for the preparation. It meets pharmacopoeial standards for sterility, pyrogen-free status, and purity.

Notably, Lidokain Aguettant is a preservative-free formulation. Unlike some older local anesthetic preparations that contain preservatives such as methylparaben or sodium metabisulfite, this product does not contain these additives. This is clinically significant because preservatives (particularly parabens) have been implicated as the cause of most “allergic reactions” reported with local anesthetics. Preservative-free formulations are preferred for neuraxial (epidural and spinal) administration and for patients with a history of sensitivity to preservatives.

The solution does not contain epinephrine (adrenaline). If the clinician determines that epinephrine should be co-administered to prolong the duration of anesthesia and reduce systemic absorption, it must be added separately at the time of preparation (typically to a final concentration of 1:200,000 or 5 µg/ml). Commercially available pre-mixed lidocaine with epinephrine formulations are also available but are separate products from Lidokain Aguettant.