Epinephrine/lidocaine/tetracaine topical Disease Interactions

Topical lidocaine is not recommended to be used in teething infants and young children, as its ingestion is dangerous and potentially fatal. Ingestion of the drug has shown to result in seizures, severe brain injury, and heart problems in children.

Lidocaine is absorbed through intact skin and mucosal membranes following topical administration. Prolonged exposure, large doses, frequent applications and/or use on compromised skin or mucosa can produce systemic effects. At high plasma levels, lidocaine can cause hypotension, bradycardia, and cardiovascular collapse. Therapy with lidocaine topical should be administered cautiously in patients with shock, sinus bradyarrhythmia, or severe heart block. The recommended dosage should not be exceeded. Children and debilitated, elderly, or acutely ill patients should be given reduced dosages commensurate with their age, weight, and physical condition.

Lidocaine topical is absorbed through intact skin and mucosal membranes. Prolonged exposure, large doses, and/or application to compromised skin or mucosa can result in elevated plasma concentrations of lidocaine. Lidocaine is rapidly and extensively metabolized by the liver. Less than 10% is eliminated unchanged in the urine. Several inactive and two active forms (MEGX and GX) have been identified. MEGX and GX exhibit antiarrhythmic and convulsant properties. The pharmacokinetic disposition of lidocaine is altered by changes in hepatic function, including hepatic blood flow. Therapy with lidocaine topical should be administered cautiously and dosing modified for patients with compromised hepatic function.

Lidocaine topical is absorbed through intact skin and mucosal membranes. Prolonged exposure, large doses, and/or application to compromised skin or mucosa can result in elevated plasma concentrations of lidocaine. Lidocaine is primarily eliminated by the kidney. Less than 10% is eliminated unchanged in the urine. Two active metabolites (MEGX and GX) have been identified that exhibit antiarrhythmic and convulsant properties. Serum concentrations of lidocaine and the active metabolites are increased and the half-life prolonged in patients with renal impairment. Therapy with lidocaine topical should be administered cautiously and dosing modified for repeated doses in patients with compromised renal function.

Lidocaine topical is absorbed through intact skin and mucosal membranes. Prolonged exposure, large doses, and/or application to compromised skin or mucosa can result in elevated plasma concentrations of lidocaine. Seizures can occur as a result of accumulation of active metabolites. Therapy with lidocaine topical should be administered cautiously to patients with or predisposed to seizure disorders.

The use of sympathomimetic amines has been infrequently associated with significant hypotension especially in dehydrated patients secondary to the drug's beta-2 mediated vasodilation. Hypovolemia should be corrected, if possible, before administering sympathomimetic amines. Blood pressure and ECG should be monitored at regular intervals. Monitoring of cardiac output and pulmonary wedge pressure may also be desired.

Acidosis, hypoxia, and hypercapnia may reduce the effectiveness of sympathomimetic amines in raising blood pressure. These conditions should be corrected before initiating therapy with sympathomimetic amines, if possible. Monitoring the patients acid-base balance, carbon dioxide levels, and oxygen saturation is recommended.