![]() ![]() If local anesthetics must be used in these patients, close monitoring for symptoms and signs of methemoglobinemia is recommended. Although all patients are at risk for methemoglobinemia, patients with glucose-6-phosphate dehydrogenase deficiency, congenital or idiopathic methemoglobinemia, cardiac or pulmonary compromise, infants under 6 months of age, and concurrent exposure to oxidizing agents or their metabolites are more susceptible to developing clinical manifestations of the condition. Lidocaine Ointment 5% should be used with extreme caution in the presence of sepsis or severely traumatized mucosa in the area of application, since under such conditions there is the potential for rapid systemic absorption.Ĭases of methemoglobinemia have been reported in association with local anesthetic use. ![]() THE MANAGEMENT OF SERIOUS ADVERSE REACTIONS MAY REQUIRE THE USE OF RESUSCITATIVE EQUIPMENT, OXYGEN, AND OTHER RESUSCITATIVE DRUGS. In the rhesus monkey arterial blood levels of 18 to 21 mcg/mL have been shown to be threshold for convulsive activity.ĮXCESSIVE DOSAGE, OR SHORT INTERVALS BETWEEN DOSES, CAN RESULT IN HIGH PLASMA LEVELS AND SERIOUS ADVERSE EFFECTS, PATIENTS SHOULD BE INSTRUCTED TO STRICTLY ADHERE TO THE RECOMMENDED DOSAGE AND ADMINISTRATION GUIDELINES AS SET FORTH IN THIS PACKAGE INSERT. Objective adverse manifestations become increasingly apparent with increasing venous plasma levels above 6 mcg free base per mL. Renal dysfunction does not affect lidocaine kinetics but may increase the accumulation of metabolites.įactors such as acidosis and the use of CNS stimulants and depressants affect the CNS levels of lidocaine required to produce overt systemic effects. The half-life may be prolonged two-fold or more in patients with liver dysfunction. Because of the rapid rate at which lidocaine is metabolized, any condition that affects liver function may alter lidocaine kinetics. Studies of lidocaine metabolism following intravenous bolus injections have shown that the elimination half-life of this agent is typically 1.5 to 2 hours. Lidocaine crosses the blood-brain and placental barriers, presumably by passive diffusion. Binding is also dependent on the plasma concentration of the alpha-l-acid glycoprotein. At concentrations of 1 to 4 mcg of free base per mL, 60 to 80 percent of lidocaine is protein bound. The plasma binding of lidocaine is dependent on drug concentration, and the fraction bound decreases with increasing concentration. The primary metabolite in urine is a conjugate of 4-hydroxy-2,6-dimethylaniline. Approximately 90% of lidocaine administered is excreted in the form of various metabolites, and less than 10% is excreted unchanged. The pharmacological/toxicological actions of these metabolites are similar to, but less potent than, those of lidocaine. N-dealkylation, a major pathway of biotransformation, yields the metabolites monoethylglycinexylidide and glycinexylidide. Biotransformation includes oxidative N-dealkylation, ring hydroxylation, cleavage of the amide linkage, and conjugation. Lidocaine is metabolized rapidly by the liver, and metabolites and unchanged drug are excreted by the kidneys. Lidocaine is also well-absorbed from the gastrointestinal tract, but little intact drug appears in the circulation because of biotransformation in the liver. In general, the rate of absorption of local anesthetic agents following topical application occurs most rapidly after intratracheal administration. They contribute $100,000 to $249,999.Lidocaine may be absorbed following topical administration to mucous membranes, its rate and extent of absorption depending upon the specific site of application, duration of exposure, concentration, and total dosage. Our Supporting partners are active champions who provide encouragement and assistance to the arthritis community. ![]() Our Signature partners make their mark by helping us identify new and meaningful resources for people with arthritis. ![]() Our Pacesetters ensure that we can chart the course for a cure for those who live with arthritis. Our Pioneers are always ready to explore and find new weapons in the fight against arthritis. These inspired and inventive champions have contributed $1,500,00 to $1,999,999. Our Visionary partners help us plan for a future that includes a cure for arthritis. Our Trailblazers are committed partners ready to lead the way, take action and fight for everyday victories. Join us today and help lead the way as a Champion of Yes. As a partner, you will help the Arthritis Foundation provide life-changing resources, science, advocacy and community connections for people with arthritis, the nations leading cause of disability. ![]()
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