Drug Interactions between cimetidine and Leva Set

Some of the medication in prilocaine topical is absorbed through the skin into the bloodstream and may cause interactions with other medications such as lidocaine topical. When used together, this combination may increase the risk of methemoglobinemia, a condition that can lead to oxygen deprivation in tissues and vital organs due to reduced oxygen-carrying capacity of the blood. Individuals may be more susceptible to developing methemoglobinemia during treatment with these medications if they are very young (especially neonates and infants) or have anemia, diseases of the heart or lungs, blood circulation disorders, liver cirrhosis, shock, sepsis, and certain genetic predispositions such as NADH cytochrome-b5 reductase deficiency, glucose-6-phosphate dehydrogenase deficiency, and hemoglobin M. In addition, excessive use of prilocaine topical such as application of large doses or on larger than recommended areas, as well as use on inflamed or abraded areas or broken skin, can increase absorption and result in high blood levels of the medication. Close medical supervision is necessary when medications that can cause methemoglobinemia are used together. Signs and symptoms of methemoglobinemia may be delayed by several hours after treatment with prilocaine topical. Patients (or their caregivers) should seek immediate medical attention if they develop a gray discoloration of the skin, mouth, or nail bed; nausea; headache; dizziness; lightheadedness; fatigue; shortness of breath; rapid or shallow breathing; a rapid heartbeat; palpitation; anxiety; or confusion. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Consumer information for this interaction is not currently available.

MONITOR: Coadministration with cimetidine may increase the plasma concentration of topical lidocaine formulations. In a study of healthy volunteers, cimetidine increased the systemic exposure (AUC) of a 10% topical lidocaine spray applied to the pharynx by 1.5-fold. The proposed mechanism for this interaction is cimetidine-mediated inhibition of CYP450 1A2 and 3A4 which are involved in the metabolism of lidocaine. The degree of systemic absorption of topical lidocaine may be dependent on the duration of application and the applied surface area.

MANAGEMENT: The potential for an interaction should be considered during concomitant use of cimetidine and topical lidocaine formulations. If coadministration is required, patients should be monitored for lidocaine-related adverse effects or toxicities including drowsiness, mental status change, or tremor.