Adverse drug reactions (ADRs) are rare when<unk>  is used as a local anesthetic and is administered correctly. Most ADRs associated with<unk>  for anesthesia relate to administration technique (resulting in systemic exposure) or pharmacological effects of anesthesia, and allergic reactions only rarely occur. Systemic exposure to excessive quantities of<unk>  mainly result in central nervous system (CNS) and cardiovascular effects – CNS effects usually occur at lower blood plasma concentrations and additional cardiovascular effects present at higher concentrations, though cardiovascular collapse may also occur with low concentrations. ADRs by system are: *CNS excitation: nervousness, agitation, anxiety, apprehension, tingling around the mouth (circumoral paraesthesia), headache, hyperesthesia, tremor, dizziness, pupillary changes, psychosis, euphoria, hallucinations, and seizures *CNS depression with increasingly heavier exposure: drowsiness, lethargy, slurred speech, hypoesthesia, confusion, disorientation, loss of consciousness, respiratory depression and apnoea. *Cardiovascular: hypotension, bradycardia, arrhythmias, flushing, venous insufficiency, increased defibrillator threshold, edema, and/or cardiac arrest – some of which may be due to hypoxemia secondary to respiratory depression. *Respiratory: bronchospasm, dyspnea, respiratory depression or arrest *Gastrointestinal: metallic taste, nausea, vomiting *Ears: tinnitus *Eyes: local burning, conjunctival hyperemia, corneal epithelial changes/ulceration, diplopia, visual changes (opacification) *Skin: itching, depigmentation, rash, urticaria, edema, angioedema, bruising, inflammation of the vein at the injection site, irritation of the skin when applied topically *Blood: methemoglobinemia *Allergy ADRs associated with the use of intravenous<unk>  are similar to toxic effects from systemic exposure above. These are dose-related and more frequent at high infusion rates (≥3 mg/min). Common ADRs include: headache, dizziness, drowsiness, confusion, visual disturbances, tinnitus, tremor, and/or paraesthesia. Infrequent ADRs associated with the use of<unk>  include: hypotension, bradycardia, arrhythmias, cardiac arrest, muscle twitching, seizures, coma, and/or respiratory depression. It is generally safe to use<unk>  with vasoconstrictor such as adrenaline, including in regions such as the nose, ears, fingers, and toes. While concerns of tissue death if used in these areas have been raised, evidence does not support these concerns. Interactions Any drugs that are also ligands of CYP3A4 and CYP1A2 can potentially increase serum levels and potential for toxicity or decrease serum levels and the efficacy, depending on whether they induce or inhibit the enzymes, respectively. Drugs that may increase the chance of methemoglobinemia should also be considered carefully. Dronedarone and liposomal morphine are both absolutely a contraindication, as they may increase the serum levels, but hundreds of other drugs require monitoring for interaction. Contraindications Absolute contraindications for the use of<unk>  include: * Heart block, second or third degree (without pacemaker) * Severe sinoatrial block (without pacemaker) * Serious adverse drug reaction to<unk>  or amide local anesthetics * Hypersensitivity to corn and corn-related products (corn-derived dextrose is used in the mixed injections) * Concurrent treatment with quinidine, flecainide, disopyramide, procainamide (class I antiarrhythmic agents) * Prior use of amiodarone hydrochloride * Adams-Stokes syndrome * Wolff-Parkinson-White syndrome *<unk>  viscous is not recommended by the FDA to treat teething pain in children and infants. Exercise caution in patients with any of these: * Hypotension not due to arrhythmia * Bradycardia * Accelerated idioventricular rhythm * Elderly * Ehlers–Danlos syndromes; efficiency of local anesthetics can be reduced * Pseudocholinesterase deficiency * Intra-articular infusion (this is not an approved indication and can cause chondrolysis) * Porphyria, especially acute intermittent porphyria;<unk>  has been classified as porphyrogenic because of the hepatic enzymes it induces, although clinical evidence suggests it is not. Bupivacaine is a safe alternative in this case. * Impaired liver function – people with lowered hepatic function may have an adverse reaction with repeated administration of<unk>  because the drug is metabolized by the liver. Adverse reactions may include neurological symptoms (e.g. dizziness, nausea, muscle twitches, vomiting, or seizures). Overdosage Overdoses of<unk>  may result from excessive administration by topical or parenteral routes, accidental oral ingestion of topical preparations by children (who are more susceptible to overdose), accidental intravenous (rather than subcutaneous, intrathecal, or paracervical) injection, or from prolonged use of subcutaneous infiltration anesthesia during cosmetic surgery. Such overdoses have often led to severe toxicity or death in both children and adults.<unk>  and its two major metabolites may be quantified in blood, plasma, or serum to confirm the diagnosis in potential poisoning victims or to assist forensic investigation in a case of fatal overdose.<unk>  is often given intravenously as an antiarrhythmic agent in critical cardiac-care situations. Treatment with intravenous lipid emulsions (used for parenteral feeding) to reverse the effects of local anaesthetic toxicity is becoming more common. Postarthroscopic glenohumeral chondrolysis<unk>  in large amounts may be toxic to cartilage and intra-articular infusions can lead to postarthroscopic glenohumeral chondrolysis.
Lidocaine
Etidocaine
Iontocaine
Pramocaine
Tocainide
Nortilidine
Quinidine
Prilocaine