Drug Interaction Report

Ritonavir may increase the blood levels of lisdexamfetamine. This may increase the risk and/or severity of side effects such as nervousness, increased heart rate and/or blood pressure, loss of appetite, and circulation problems in your fingers and toes. Combining these medications can also increase the risk of seizures, especially if both medications are associated with an increased seizure risk. The risk of getting a rare but serious condition called serotonin syndrome, which has been seen with lisdexamfetamine, might also be increased. Symptoms of serotonin syndrome include confusion, hallucination, seizure, extreme changes in blood pressure, increased heart rate, fever, excessive sweating, shivering or shaking, blurred vision, muscle spasm or stiffness, tremor, incoordination, stomach cramps, nausea, vomiting, and diarrhea. Severe cases may result in coma and even death. You should contact your doctor immediately if you experience these symptoms while taking the medications. 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.

Ritonavir should be taken with food to lessen gastrointestinal side effects. It is important that you take this medication exactly as prescribed by your doctor. Do not change your treatment or stop treatment without first talking to your doctor.

Using lisdexamfetamine together with alcohol can increase the risk of cardiovascular side effects such as increased heart rate, chest pain, or blood pressure changes. You should avoid or limit the use of alcohol while being treated with lisdexamfetamine. Let your doctor know if you experience severe or frequent headaches, chest pain, and/or a fast or pounding heartbeat. 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.

Food significantly increases the absorption of paritaprevir. You should take each dose of paritaprevir with a meal. Taking it on an empty stomach may lead to inadequate blood levels and reduced effectiveness of the medication.