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Drug Interactions between Nalphen and Symtuza

This report displays the potential drug interactions for the following 2 drugs:

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Interactions between your drugs

Moderate

phenylephrine phenylpropanolamine

Applies to: Nalphen (chlorpheniramine / phenylephrine / phenylpropanolamine / phenyltoloxamine) and Nalphen (chlorpheniramine / phenylephrine / phenylpropanolamine / phenyltoloxamine)

Both phenylephrine and phenylpropanolamine can increase blood pressure and heart rate, and combining them may enhance these effects. Talk to your doctor before using these medications, especially if you have a history of high blood pressure or heart disease. 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.

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Moderate

chlorpheniramine phenyltoloxamine

Applies to: Nalphen (chlorpheniramine / phenylephrine / phenylpropanolamine / phenyltoloxamine) and Nalphen (chlorpheniramine / phenylephrine / phenylpropanolamine / phenyltoloxamine)

Using chlorpheniramine together with phenyltoloxamine may increase side effects such as drowsiness, blurred vision, dry mouth, heat intolerance, flushing, decreased sweating, difficulty urinating, abdominal cramping, constipation, irregular heartbeat, confusion, and memory problems. Side effects may be more likely to occur in the elderly or those with a debilitating condition. You should avoid or limit the use of alcohol while being treated with these medications. Also avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medications affect you. Talk to your doctor if you have any questions or concerns. 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.

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Moderate

tenofovir darunavir

Applies to: Symtuza (cobicistat / darunavir / emtricitabine / tenofovir alafenamide) and Symtuza (cobicistat / darunavir / emtricitabine / tenofovir alafenamide)

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.

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Moderate

chlorpheniramine cobicistat

Applies to: Nalphen (chlorpheniramine / phenylephrine / phenylpropanolamine / phenyltoloxamine) and Symtuza (cobicistat / darunavir / emtricitabine / tenofovir alafenamide)

Cobicistat may increase the blood levels and effects of chlorpheniramine. 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.

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Moderate

tenofovir cobicistat

Applies to: Symtuza (cobicistat / darunavir / emtricitabine / tenofovir alafenamide) and Symtuza (cobicistat / darunavir / emtricitabine / tenofovir alafenamide)

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.

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Moderate

emtricitabine cobicistat

Applies to: Symtuza (cobicistat / darunavir / emtricitabine / tenofovir alafenamide) and Symtuza (cobicistat / darunavir / emtricitabine / tenofovir alafenamide)

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.

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Drug and food interactions

Moderate

chlorpheniramine food

Applies to: Nalphen (chlorpheniramine / phenylephrine / phenylpropanolamine / phenyltoloxamine)

Alcohol can increase the nervous system side effects of chlorpheniramine such as dizziness, drowsiness, and difficulty concentrating. Some people may also experience impairment in thinking and judgment. You should avoid or limit the use of alcohol while being treated with chlorpheniramine. Do not use more than the recommended dose of chlorpheniramine, and avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medication affects you. Talk to your doctor or pharmacist if you have any questions or concerns.

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Moderate

phenylpropanolamine food

Applies to: Nalphen (chlorpheniramine / phenylephrine / phenylpropanolamine / phenyltoloxamine)

Using phenylpropanolamine with alcohol can increase the risk of cardiovascular side effects such as increased heart rate, chest pain, or blood pressure changes. In addition, you may also be more likely to experience nervous system side effects such as dizziness, drowsiness, depression, and difficulty concentrating. You should avoid or limit the use of alcohol while being treated with phenylpropanolamine. Do not use more than the recommended dose of phenylpropanolamine, and avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medication affects you. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medication without first talking to your doctor.

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Moderate

phenyltoloxamine food

Applies to: Nalphen (chlorpheniramine / phenylephrine / phenylpropanolamine / phenyltoloxamine)

Alcohol can increase the nervous system side effects of phenyltoloxamine such as dizziness, drowsiness, and difficulty concentrating. Some people may also experience impairment in thinking and judgment. You should avoid or limit the use of alcohol while being treated with phenyltoloxamine. Do not use more than the recommended dose of phenyltoloxamine, and avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medication affects you. Talk to your doctor or pharmacist if you have any questions or concerns.

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Moderate

darunavir food

Applies to: Symtuza (cobicistat / darunavir / emtricitabine / tenofovir alafenamide)

Food can enhance the levels of darunavir in your body. Take darunavir with food. The type of food does not matter. This will make it easier for your body to absorb the medication. Swallow the whole tablets with a drink such as water or milk. Do not chew the tablets. Darunavir must be always be taken together at the same time as another medication called ritonavir (Norvir).

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Moderate

phenylephrine food

Applies to: Nalphen (chlorpheniramine / phenylephrine / phenylpropanolamine / phenyltoloxamine)

Both phenylephrine and caffeine can increase blood pressure and heart rate, and combining them may enhance these effects. Talk to your doctor before using these medications, especially if you have a history of high blood pressure or heart disease. 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.

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Moderate

phenylpropanolamine food

Applies to: Nalphen (chlorpheniramine / phenylephrine / phenylpropanolamine / phenyltoloxamine)

Both phenylpropanolamine and caffeine can increase blood pressure and heart rate, and combining them may enhance these effects. Talk to your doctor before using these medications, especially if you have a history of high blood pressure or heart disease. 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.

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Minor

tenofovir food

Applies to: Symtuza (cobicistat / darunavir / emtricitabine / tenofovir alafenamide)

Information for this minor interaction is available on the professional version.

Therapeutic duplication warnings

No warnings were found for your selected drugs.

Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.


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Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No interaction information available.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.