Vignocaine Viscous

Lignocaine hydrochloride.

Each ml contains: Lignocaine HCl 20mg (2% w/v).
Preservatives: Methyl Hydroxybenzoate 0.12% w/v, Propyl Hydroxybenzoate 0.012% w/v.
Does not contain alcohol.

Pharmacology: Pharmacodynamics: Lignocaine stabilises the neuronal membrane and prevents the initiation and conduction of nerve impulses, thereby effecting local anaesthetic action.
The onset of action occurs within 3-5 minutes on mucous membranes. Its low surface tension ensures an even film over the surface of the mucous membrane so that the lignocaine comes into intimate contact with the total surface. High viscosity ensures sufficiently prolonged contact with the mucous membrane. It is ineffective when applied to intact skin.
Pharmacokinetics: Lignocaine is readily absorbed from the gastrointestinal tract, from mucous membranes, and through damaged skin . The rate of absorption is most rapid after intratracheal administration and the absorption through intact skin is poor. It is weak bases and able to diffuse through connective tissues and cellular membranes at tissue's pH to reach nerve fibre where ionization can occur. In general, its rate and extent of absorption will depend on concentration and total dose administered, the specific site of application and duration of exposure.
Lignocaine is bound to plasma proteins, including α1-acid glycoprotein (AAG). The extent of binding is variable but is about 66%. Plasma protein binding of lignocaine depends in part on the concentrations of both lignocaine and AAG. Any alteration in the concentration of AAG can greatly affect plasma concentrations of lignocaine. The fraction bound decrease with increasing drug concentration. AAG is increased after trauma, surgery, burns, myocardial infarction, in chronic inflammatory disorders such as Crohn's disease and in cancer. Protein binding may therefore be greatly increased in these conditions and reduced in neonates, the nephrotic syndrome and in liver disease when AAG concentrations are lower than normal. This can result in an eightfold variation in the free fraction of lignocaine between these conditions. AAG concentrations may also be reduced by oestrogens leading to a higher free fraction of lignocaine in women than in men and the free fraction is further increased during pregnancy and in women taking oral contraceptives. Protein binding may also be affected by other concomitant drug therapy or smoking.
Lignocaine has biphasic elimination half-life with initial 7 to 30 minutes and terminal 1.5 to 2 hours. Lignocaine is largely metabolised in the liver and any alteration in liver function or hepatic blood flow can have a significant effect on its pharmacokinetics and dosage requirements. First-pass metabolism is extensive and bioavailability is about 35% after oral doses. Metabolism in the liver is rapid and about 90% of a given dose is dealkylated to form monoethylglycinexylidide and glycinexylidide. Both of these metabolites may contribute to the therapeutic and toxic effects of lignocaine and since their half-lives are longer than that of lignocaine. Further metabolism occurs and metabolites are excreted in the urine with less than 10% of unchanged lignocaine. Reduced clearance of lignocaine has been found in patients with heart failure, alcoholic liver disease, or chronic or viral hepatitis.

Vignocaine 2% w/v Viscous Solution is indicated as topical anaesthesia for: Introduction of instruments and catheters into the respiratory and digestive tracts, e.g. bronchoscopy, oesophagoscopy; Irritated or inflamed mucous membranes of the mouth and pharynx, e.g. lesions following tonsillectomy; Painful diseases of the upper gastrointestinal tract, e.g. oesophagitis.

For oral administration only.
The dosages given as follows are guidelines, and the dosage must be adapted to the individual patient. Be aware of the total dose in cases of combination with other medicinal products that contain lignocaine.
Adults: Insertion of tubes and catheters into the stomach: 10-15 ml (200-300 mg lignocaine) are swallowed.
Irritated or inflamed mucous membranes in the mouth: 5-15 ml (100-300 mg lignocaine) are rinsed around in the mouth. The solution is then spat out. In dental practice 10 ml solution (200 mg lignocaine) are used. The solution should be spat out when adequate anaesthesia has been achieved (after approx. 1 minute).
Irritated or inflamed mucous membranes in the pharynx: 5-10 ml (100-200 mg lignocaine) are gargled with , after which the solution is slowly swallowed.
Painful conditions in the upper gastrointestinal tract: 5-15 ml (100-300 mg lignocaine) are rapidly swallowed all at once.
The daily dose should not exceed 1200 mg, which is equivalent to a total of 60 ml.
If Vignocaine 2% w/v Viscous Solution is combined with other lignocaine products, the total dose of lignocaine on one dosing occasion should not exceed 400 mg.

The most serious effects of lignocaine intoxication are on the central nervous system (CNS) and cardiovascular system and overdosage can result in severe hypotension, asystole, bradycardia, apnoea, seizures, coma, cardiac arrest, respiratory arrest and death. Although the bioavailability of lignocaine is low it may be sufficient to result in significant toxicity when swallowed and there have been reports of CNS effects, seizures, and death in children and adults after the ingestion of topical solutions and after the use of viscous preparations in the mouth. Lignocaine is absorbed from mucous membranes and serious toxicity has been reported after urethral or rectal instillation of lignocaine preparations.
The first consideration is prevention, best achieved by careful and constant monitoring of cardiovascular and respiratory vital signs and the patient's state of consciousness after each local anaesthetic administration. Severe neurological symptoms such as convulsion and CNS depression must be treated symptomatically by administration of anti-convulsive drugs, respiratory support by maintenance of a patent airway and assisted ventilation with oxygen. Circulatory depression must be treated with supportive treatment which may require administration of intravenous fluids and, when appropriate, a vasopressor (e.g. ephedrine) as indicated by clinical situation. Immediate cardiopulmonary resuscitation should be instituted if circulatory arrest occurs.

Lignocaine is contraindicated in patients with known hypersensitivity to lignocaine or other local anaesthetics of amide type.

If symptoms persist, please consult a doctor.
Patients should strictly adhere to the prescribed dose and frequency of administration to reduce the risk of serious undesirable events with the use of lignocaine. Excessive dosage or short interval between dose can result in high plasma level and serious undesirable effects.
Lignocaine is not suitable for patients with hypovolaemia, heart block or other conduction disturbances.
Lignocaine should be used with caution if mucosa in area of application has been traumatized due to potential for rapid systemic absorption.
Reduced dose should be given to debilitated, elderly patients, acutely ill patients and children according to their age, weight and physical condition.
Lignocaine should be used with caution in patients with congestive heart failure, bradycardia, or respiratory depression.
Lignocaine should be given with caution in patient with hepatic impairment because it is extensively metabolised in liver. Patients with conditions that reduce hepatic blood flow such as cardiac and circulatory failure may have prolonged lignocaine plasma half-life. Metabolites of lignocaine may accumulate in patients with renal impairment.
Lignocaine considered as a potential triggering agent for familial malignant hyperthermia. It has been shown that the use of amide local anaesthetics in malignant hypothermia patients is generally safe, but cases of malignant hyperthermia have been occasionally documented after use.
When used for endotracheal tube lubrication care should be taken to avoid introduction of the viscous solution into the lumen of the tube. The solution may dry on the inner surface leaving residue which tends to clump with flexion, narrowing the lumen. There have been rare reports in which this residue has caused the lumen to occlude.
Lignocaine may impair swallowing and lead to danger of aspiration. Hence, food should not be ingested for 60 minutes after use of lignocaine in mouth or throat area. This is especially important in children because of their frequency of eating.
Numbness of tongue or buccal mucosa may increase danger of biting trauma. For this reason food and/or chewing gum should not be used while the mouth or throat area is anesthetized.
Effects on Ability to Drive and Use Machines: Depending on the dose, local anaesthetics may have a very mild effect on mental function and may temporarily impair locomotion and coordination.

Lignocaine crosses the placenta barrier and there are no adequate and well-controlled studies in pregnant women. Serious adverse effects of epidural anaesthesia are rare. Lignocaine blood levels after normal doses are low when used for surface anaesthesia. Hence, only little drug is available for placenta transfer. However, lignocaine may have transient effects on the neonatal auditory system. Lignocaine should be used in pregnancy only if clearly needed.
Lignocaine is distributed into breast milk. No adverse effect is seen in breastfed infants whose mothers were taking lignocaine.
Use at recommended doses is unlikely to affect the neonate.

Drowsiness is usually an early sign of high blood level of lignocaine and may occur as a consequence of rapid absorption. Lignocaine may associate with increased risk of neurotoxic complications when used as spinal anaesthesia. Signs of cerebral ataxia have been reported with topical use of lignocaine for endoscopy.
Undesirable effect on CNS can be excitatory and/or depressant and may be characterized by nervousness, light-headedness, apprehension, euphoria, confusion, drowsiness, dizziness, tinnitus, blurred or double vision, vomiting, sensations of heat, cold or numbness, twitching, tremors, convulsions, unconsciousness, respiratory depression and arrest.
Cardiovascular may depress and characterize by bradycardia, hypotension, cardiovascular collapse which may lead to cardiac arrest.
Allergic reactions as a result of sensitivity to lignocaine are extremely rare and are characterized by cutaneous lesions, oedema, urticaria or anaphylactoid reactions.

Propranolol and cimetidine may reduce clearance of lignocaine. Cardiac depressant effects of lignocaine are additive with beta blockers and antiarrhythmics. Besides, additive cardiac effects may occur when lignocaine is given with IV phenytoin.
Long-term use of phenytoin or other enzyme-inducers may increase dosage requirement of lignocaine. Acetazolamide, loop diuretics and thiazides produce hypokalaemia which antagonises effect of lignocaine.

Store below 30°C. Protect from light. Keep cap tightly closed.
Shelf-Life: 2 years from the date of manufacture.

Anaesthetics - Local & General

N01BB02 - lidocaine ; Belongs to the class of amides. Used as local anesthetics.

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