Drug Interactions between ifosfamide / mesna and ropivacaine / sufentanil

MONITOR: Centrally-acting agents such as antiemetics, sedatives, narcotics, or antihistamines may add to the neurotoxic effects of ifosfamide. Administration of ifosfamide can cause CNS toxicity, which necessitates careful monitoring of the patient. Neurologic manifestations include somnolence, confusion, hallucinations, blurred vision, psychotic behavior, extrapyramidal symptoms, urinary incontinence, seizures, and in some instances, coma. There have also been reports of peripheral neuropathy. Ifosfamide neurotoxicity may occur within a few hours to a few days after initial administration and typically resolves within 48 to 72 hours of ifosfamide discontinuation. However, symptoms may persist for longer periods of time, and recovery has occasionally been incomplete. Fatal outcomes have been reported. There have also been reports of recurrence of CNS toxicity after several uneventful treatment courses.

MANAGEMENT: Due to the potential for additive effects, centrally-acting agents should be used with caution in combination with ifosfamide. Patients should be advised to avoid driving, operating machinery, or engaging in potentially hazardous activities requiring mental alertness and motor coordination until they know how the medications affect them. If ifosfamide-induced encephalopathy occurs, both ifosfamide and non-essential concomitant CNS agents should be discontinued. Supportive therapy should be initiated and maintained until complete resolution of neurotoxicity.

Switch to consumer interaction data

MONITOR: Coadministration of local anesthetics with other oxidizing agents that can also induce methemoglobinemia such as antimalarials (e.g., chloroquine, quinine), nitrates and nitrites, sulfonamides, aminosalicylic acid, dimethyl sulfoxide (DMSO), metoclopramide, nitrofurantoin, phenazopyridine, phenobarbital, and phenytoin may increase the risk. Additional risk factors include very young age (e.g., infants less than 6 months), cardiac or pulmonary disease, genetic predisposition, and glucose-6-phosphate dehydrogenase (G6PD) deficiency. Data surrounding the incidence of methemoglobinemia are agent-specific and, in many instances, have primarily been reported in case reports and/or in overdose situations.

MANAGEMENT: Monitoring for signs and symptoms of methemoglobinemia is recommended if local anesthetics must be used with other methemoglobin-inducing agents. 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.

Switch to consumer interaction data