LIDOTHOL

Clinical summary

Indications and usage INDICATIONS AND USAGE: Lidothol is a formulation used to assist patients in the treatment of mild to moderate acute or chronic aches or pain. Muscle or joint pain can be due to muscle or ligament strains, simple backache, tendonitis, osteoarthritis, rheumatoid arthritis, peripheral neuropathies such as diabetic neuropathy or post herpetic neuralgia, and other complex regional pains. It can also be used to help with certain types of headaches, but use with caution when applying in order to avoid eye contact. Other uses may be considered if deemed clinically relevant. Dosage and administration DOSAGE AND ADMINISTRATION: Apply Lidothol to intact skin to cover the most painful area. Apply no more than four patches per day. Each patch should not be applied for more than 12 hours in a given 24-­‐ hour period. Patches may be cut into smaller sizes with scissors prior to removal of the protective film. Clothing may be worn over the area of application. Smaller areas of treatment are recommended in a debilitated patient, or a patient with impaired elimination. If irritation or a burning sensation occurs during application, remove the patch and do not reapply until the irritation subsides. When Lidothol is used concurrently with other products containing local anesthetic agents, the amount absorbed from all formulations must be considered. Lidothol may not stick if it gets wet. Avoid contact with water, such as bathing, swimming or showering. Warnings and cautions WARNINGS AND PRECAUTIONS Methemoglobinemia Cases of methemoglobinemia have been reported in association with local anesthetic use. 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. If local anesthetics must be used in these patients, close monitoring for symptoms and signs of methemoglobinemia is recommended. Signs and symptoms of methemoglobinemia may occur immediately or may be delayed some hours after exposure and are characterized by a cyanotic skin discoloration and abnormal coloration of the blood. Methemoglobin levels may continue to rise; therefore, immediate treatment is required to avert more serious central nervous system and cardiovascular adverse effects, including seizures, coma, arrhythmias, and death. Discontinue Lidothol and any other oxidizing agents. Depending on the severity of the symptoms, patients may respond to supportive care, i.e., oxygen therapy, hydration. More severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. Drug interactions DRUG INTERACTIONS Patients that are administered local anesthetics may be at increased risk of developing methemoglobinemia when concurrently exposed to the following oxidizing agents Class Nitrates/Nitrites Local Anesthetics Antineoplastic agents Antibiotics Antimalarials Anticonvulsants Other drugs Examples nitroglycerin, nitroprusside, nitric oxide, nitrous oxide benzocaine, lidocaine, bupivacaine, mepivacaine, tetracaine, prilocaine, procaine, articaine, ropivacaine cyclophosphamide, flutamide, rasburicase, ifosfamide, hydroxyurea dapsone, sulfonamides, nitrofurantoin, para-aminosalicyclic acid chloroquine, primaquine phenytoin, sodium valproate, phenobarbital acetaminophen, metoclopramide, sulfa drugs (i.e., sulfasalazine), quinine