Drug Interaction Report

Using ublituximab together with ethotoin may increase the risk of serious infections. Talk to your doctor if you have any questions or concerns. Of particular concern is an infection known as progressive multifocal leukoencephalopathy (PML), which is a rare but serious viral infection of the brain that may lead to disability and death. Your doctor may already be aware of the risks but has determined that this is the best course of treatment for you and has taken appropriate precautions and is monitoring you closely for any potential complications. Let your doctor know if you develop signs and symptoms of infection such as fever, chills, sore throat, shortness of breath, blood in phlegm, weight loss; yellow skin, severe fatigue, diarrhea, vomiting, body aches; and pain or burning during urination. Also, seek immediate medical attention if you experience progressive weakness on one side of the body, clumsiness of limbs, disturbance of vision, confusion, or changes in thinking, memory, and personality, as these may be early symptoms of PML. 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.

Ethotoin levels may decrease when the suspension is given with enteral feedings. This could lead to a loss of seizure control. You could interrupt the feeding for 2 hours before and after the ethotoin dose. Alternatively, you may give the ethotoin suspension diluted in water and flush the tube with water after administration. These would make it easier for your body to absorb the medication. However, this still may not entirely avoid the interaction and may not always be feasible. You should have your ethotoin levels checked upon starting and stopping of enteral feedings. In addition, using ethotoin together with food may alter the effects of ethotoin. Contact your doctor if you experience worsening of seizure control or symptoms of toxicity, including twitching eye movements, slurred speech, loss of balance, tremor, muscle stiffness or weakness, nausea, vomiting, feeling light-headed, fainting, and slow or shallow breathing. If your doctor does prescribe these medications together, you may need a dose adjustment or special test to safely use both medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Ask your doctor before making any changes to your therapy.