Lidonaline

Category: Anesthetic agent

Pharmaceutics form: sterile injectable solution.

Composition: each ml contains lidocaine HCl 20mg, noradrenaline 0.08mg

MECHANISM OF ACTIONS.
Local anesthetics are generally water-soluble acid salts. When these salts are injected into tissues that normally are slightly alkaline. The acid salt form of the local anesthetic is neutralized. This releases the free amine or alkaloidal base through hydrolysis, which is necessary before the drug can penetrate the lipid barrier of the cell membrane to induce anesthesia. Local anesthetics decrease cell membrane permeability. The amino groups the classic local anesthetic drugs interact with the polar groups of the cell membrane to decrease membrane permeability of the nerve cell and stabilize the membrane forces. As a result, diffusion of potassium and sodium ions cannot occur, and changes that give rise to the nerve impulses are blocked.

Effects of Noradrenalin:
Constriction of blood capillaries near the site of injection of a local anesthetic decreases rate of absorption and thereby prolongs the period of action of the drug. In addition to prolonging anesthetic action, a vasoconstrictor decreases toxicity of a local anesthetic by delaying absorption and preventing high blood concentrations. Slower absorption provides more time for destruction of local anesthetic by tissues of the body. Thus a toxic concentration in the blood stream is less probable.

PHARMACOKINETICS:
Lidocaine is metabolized primarily in the liver at a rate nearly as rapid as that for procaine. The unchanged form is excreted in urine of the in a concentration of 10-20%. Two metabolites have been identified in the dog from hepatic N-deethylation of lidocaine.One of these, mono ethylglyceine xylidide possesses significant pharmacologic activity, after a second N-deethylation, glycine xylidide is formed. Following loss of an ethyl group from its diethyl-amino group, lidocaine is hydrolyzed, hydrolysis will not occur until this happens. A large amount of lidocaine is conjugated with sulfate and excreted in this form.

INDICATIONS:
Lidocaine is used for infiltration, nerve conduction, epidural, and topical anesthesia in animal.

CLINICAL USE:
1-Infiltration anesthesia:infiltration anesthesia is the most common method and consists of making numerous subcutaneous injections of small volumes of local anesthetic solution into the tissues.
2-Epidural anesthesia:
Epidural anesthesia is produced by injecting local anesthetic solution into the epidural space of the spinal canal at the level of the lumbosacral region
3-Spinal anesthesia:
4-Paravebrtebral anesthesia
DOSAGE: 5- Never Block Anesthesia

1-Dogs and cats:
Epidural analgesia: 1ml per 4.5kg bodyweight
2-Goats:lidocaine has been used in cornual nerve blocks: 2ml are injected at each site to block lacrimal and infratrochlear branches of the cornual nerve.
3-Sheep: epidural anesthesia: 8-12ml
4-Cattle: low epidural analgesia: 0.5-1ml per 50kg bodyweight.
High epidural analgesia: 1ml per 5kgbodyweight.
5-Horses: for mandibular nerve blockage: 20ml desensitize the mandible, lower molars, incisors, and lower lips.
Epidural Anesthesia: 5-10ml.

ADVERSE AND COMMON SIDE EFFECTS:
With drug overdose drowsinese, tremors, nystagmus, seizure, hypotension, and increased atrioventricular conduction with atrial flutter and fibrillation have been reported. The neurological signs can be controlled with diazepam. Hypokalemia reduces antiarrhythmic effects. Avoid accidental intravascular injection. Care should be taken in the administration of repeat doses in cases where the desired degree of anesthesia has not been attained.

WITHDRAWAL TIME:
Meat & milk: 24 to36 hours after last injection.

PHARMACEUTICAL PRECAUTIONS:
Store below 30°C, protected from light. Do not freeze.
Keep out of the reach of children.

Package quantities: multidose vials of 100ml.