Drug Interactions between cobicistat / darunavir / emtricitabine / tenofovir alafenamide and dextroamphetamine

Cobicistat may increase the blood levels of dextroamphetamine. 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 dextroamphetamine, 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.

Using tenofovir together with darunavir may increase the plasma concentrations of both medicines. You may need a special test or more frequent monitoring by your doctor to safely use both medications. Contact your doctor if your condition changes or you experience increased side effects such as kidney problems. 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.

Using cobicistat together with tenofovir can increase the effects of tenofovir, which can cause new or worse kidney problems. You may need a dose adjustment or more frequent monitoring by your doctor to safely use both medications. Contact your doctor if your condition changes or you experience increased side effects. 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.

Cobicistat is a medication used to boost the effects of some medications that treat HIV infection. However, using cobicistat together with other HIV medications, such as emtricitabine, may alter the blood levels and effects of both medications. Using emtricitabine with cobicistat may reduce or increase blood levels of cobicistat. Reduced blood levels of cobicistat may make cobicistat less effective and may cause overall HIV treatment to be less effective. Cobicistat may increase blood levels of emtricitabine which may increase the risk of side effects. Talk to your doctor or pharmacist if you have any questions on how to use these medications properly. Your doctor may be able to prescribe alternatives that do not interact, or you may need a dose adjustment or more frequent monitoring to safely use both medications. Contact your doctor if your condition changes or you experience increased side effects. 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.