Drug Interactions between hydromorphone / ropivacaine and Isocaine with Levonordefrin

Consumer information for this interaction is not currently available.

MONITOR CLOSELY: Coadministration of amide local anesthetics (e.g., lidocaine, bupivacaine, ropivacaine) with other amide local anesthetics can increase the risk of developing methemoglobinemia, and may also have additive cardiac effects (e.g., bradycardia, chest pain, heart block, arrhythmias, ECG abnormalities, cardiac arrest). Individual product labeling warns that patients who are administered local anesthetics are at increased risk of developing methemoglobinemia when concurrently exposed to other local anesthetics. Additional risk factors for methemoglobinemia include very young age (e.g., infants less than 6 months), cardiac or pulmonary disease, genetic predisposition, and glucose-6-phosphate dehydrogenase (G6PD) deficiency.

MANAGEMENT: If coadministration of amide-type local anesthetics with other amide-type local anesthetics is required, caution and clinical monitoring are recommended for signs and symptoms of methemoglobinemia and additive cardiac effects. Advise patients to contact their physician if they experience adverse effects such as chest pain, palpitations, nausea, vomiting, lightheadedness, nervousness, dizziness, or tremors. Signs and symptoms of methemoglobinemia may occur immediately or hours after drug exposure. Patients or their caregivers should be advised to seek medical attention if they notice signs and symptoms of methemoglobinemia (e.g., cyanotic skin discoloration, abnormal blood coloration, nausea, headache, dizziness, lightheadedness, lethargy, fatigue, dyspnea, tachypnea, tachycardia, palpitation, anxiety, and confusion). In severe cases, patients may progress to central nervous system depression, stupor, seizures, acidosis, cardiac arrhythmias, syncope, shock, coma, and death. Methemoglobinemia should be considered if central cyanosis is unresponsive to oxygen. Calculated oxygen saturation and pulse oximetry are generally not accurate in the setting of methemoglobinemia. The diagnosis can be confirmed by an elevated methemoglobin level of at least 10% using co-oximetry. Methemoglobin concentrations greater than 10% of total hemoglobin will typically cause cyanosis, and levels over 70% are frequently fatal. However, symptom severity is not always related to methemoglobin levels. Experts suggest that treatment of methemoglobinemia varies from supplemental oxygen and symptom support to the administration of methylene blue, depending on severity of symptoms and/or the presence of G6PD deficiency. Institutional guidelines and/or individual product labeling should be consulted for further guidance on methemoglobinemia treatment.