Epinephrine + Lidocaine information from DrugsUpdate  

Pharmacodynamics

Pharmacokinetics

Lidocaine is a local anaesthetic which decreases permeability of sodium ions, blocking induction and conduction of nerve impulses. Combination with epinephrine restricts systemic spread of lidocaine, vascular absorption and its duration of local anaesthetic effect.

Onset
Peak effect: approx 5 min.

Duration
Approx 2 hours; dose and anaesthetic procedure dependant.

Absorption
Topical: lidocaine: minimal; epinephrine: minimal; readily absorbed from GI tract, mucous membranes, damaged skin, inj sites including muscle.

Distribution
Crosses placenta and blood-brain barrier. Volume of distribution: lidocaine: 1.1-2.1 L/kg, altered by many patient factors eg CHF, liver disease. Protein binding: lidocaine: 60-80% to α1 acid glycoprotein.

Metabolism
Lidocaine: 90% via hepatic 1st pass metabolism to active metabolites which can cause CNS toxicity. Epinephrine: metabolised by monoamine oxidase and catechol-o-methyltransferase taken up in the adrenergic neuron; circulating ephedrine is hepatically metabolised.

Excretion
Lidocaine: elimination half life: 2 hours; excreted via urine (<10% unchanged). Ephedrine: excreted via urine as inactive metabolites and small amounts of unchanged drug.

Epinephrine + Lidocaine Indications / Epinephrine + Lidocaine Uses

Information Not Available

Epinephrine + Lidocaine Adverse Reactions / Epinephrine + Lidocaine Side Effects

Severity of adverse effects in CNS and CVS are directly related to blood levels of lidocaine; the effects are more likely to occur after systemic administration rather than infiltration; dizziness; muscle twitching; local anaesthetic of mouth/throat impairs swallowing and increases the risk of aspiration (patients cautioned against eating or drinking for 3-4 hr after anaesthesia); transient effect on auditory system of neonate; erythema; pigmentation; pain; headache; palpitations; local necrosis; pulmonary oedema; hyperglycaemia; bradycardia; reduced cardiac output; anxiety. Epidural may cause hypotension, bradycardia, nausea and vomiting. Intraoral inj may cause stress reactions such as diaphoresis, palpitation, hyperventilation, generalised pallor and faintness. Topically: papules, burns, rash, skin irritation, burning sensation and blanching.

Potentially Fatal: Severity of adverse effects in CNS and CVS related to blood levels of lidocaine; effects more likely to occur after systemic administration rather than infiltration. CNS toxicity (due to inadvertent IV admin), medullary depression with tonic & clonic convulsions; ventricular fibrillation; severe hypertension with cerebral haemorrhage and pulmonary oedema; unconsciousness; possibly respiratory arrest. Allergic reactions including anaphylactic symptoms and possibly life threatening asthmatic episodes in susceptible patients may occur due to sodium metabisulphate constituent. Central nerve blocks may cause CV depression (especially in hypovolaemia). Retrobulbar inj may reach subarachnoid space causing CV collapse, apnoea, convulsions, temporary blindness. Paracervical block may cause foetal bradycardia/tachycardia (careful monitoring of foetal heart rate is necessary).

Precautions

Information Not Available

Special Precautions

Epilepsy, impaired cardiac conduction, CHF, DM, closed angle glaucoma, impaired liver function (if site of admin is likely to result in high blood levels), severe renal dysfunction. Local anaesthetic effect may be reduced if injected into an inflamed or infected area. Cerebrovascular insufficiency, hyperthyroidism. Neonates, elderly, patients in poor general condition (optimise patient's condition before major block), pregnancy.

Other Drug Interactions

Significance of interaction depends on route of delivery and systemic exposure; lidocaine prolongs duration of action of suxamethonium; benzodiazepines & barbiturates raise the convulsive threshold to lidocaine; vasopressors potentiate pressor effects of adrenaline; BP may increase with non-selective β-blockers, TCAs, halogenated inhalational anaesthetics and α-blockers; general anaesthetics may increase sensitivity of myocardium to dysrhythmic effects of epinephrine; lidocaine may increase levels and effects of benzodiazepines, calcium channel blockers, ciclosporine, aminophylline, fluvoxamine, mexiletine, mirtazapine, ropinirole, theophylline, trifluoperazine, dextromethorphan, fluoxetine, nefazodone, paroxetine, risperidone, TCAs and venlafaxine. Levels and effects of lidocaine may be increased by propranolol, chlorpromazine, delavirdine, fluoxetine, miconazole, pergolide, quinidine, quinine, ritonavir, ropinirole, cimetidine, azole antifungals, clarithromycin, diclofenac, doxycycline, erythromycin, isoniazid, nicardipine and verapamil. Lidocaine may decrease levels and effects of codeine, hydrocodone, oxycodone, tramadol, carbamazepine, nafcillin, nevirapine, phenobarbital, phenytoin and rifamycins. Midazolam, cisapride, ergot alkaloids, lovastatin and simvastatin are not recommended in combination with lidocaine.

Potentially Fatal: Possible additive cardiac effects with amiodarone (ECG monitoring should be considered).

Other Interactions

Food Interactions

St John's Wort may reduce lidocaine level, avoid; ephedra and yohimbe may cause CNS stimulation, avoid. 

Dosage

Injection
Local or regional anaesthesia, nerve blocks, epidural and caudal anaesthesia
Adult: Per ml prep contains lidocaine HCl 20 mg and epinephrine 5 mcg. Dosage depends on several factors such as route, type and extent of surgical procedure, duration of anaesthesia and patient's condition and age. Max dose of lidocaine given with epinephrine: 7 mg/kg and not >500 mg.
Child: 3 mth-12 yr: Per ml prep contains lidocaine HCl 20 mg and epinephrine 5 mcg. Dosage depends on several factors such as route, type and extent of surgical procedure, duration of anaesthesia and patient's condition and age. Max dose 3 mg/kg. Ideal body weight should be used in children with high body weight.

Reconstitution
Can be diluted if necessary in glucose 5%, sodium chloride 0.9% and lactated Ringer's solution.

Incompatibility
Y-site administration: ampicillin, thiopental, ampthotericin B cholesteryl sulphate complex; in syringe: cefazolin, sodium bicarbonate; when admixed: aminophylline, hyaluronidase, mephentemine, amphotericin B, decarbazine, methohexital and thiopental.

Food(before/after)

Information Not Available

Epinephrine + Lidocaine and Pregnancy

Caution when used during pregnancy

Epinephrine + Lidocaine and Lactation

Caution when used in lactation

It is not known whether this drug is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when lidocaine is administered to a nursing woman.

Epinephrine + Lidocaine and Children

Dosages in pediatric patients should be reduced, commensurate with age, body weight and physical condition.

Epinephrine + Lidocaine and Geriatic

Information Not Available

Epinephrine + Lidocaine and Other Contraindications

Tachycardia, hypertension, cerebral arteriosclerosis, ischaemic heart disease, IV admin, anaesthetise digits or appendages, myasthenia gravis.

Storage

Injection
Protect from light. Transdermal systems: 20-25 °C.

Injection
Store at 2-8 °C and discard within 3 days of opening.

Lab interference

Injection
Protect from light. Transdermal systems: 20-25 °C.

Injection
Store at 2-8 °C and discard within 3 days of opening.