This report displays the potential drug interactions for the following 2 drugs:
- Sudafed PE Nighttime Cold (acetaminophen/diphenhydramine/phenylephrine)
- Vicks NyQuil Severe Cold & Flu (acetaminophen/dextromethorphan/doxylamine/phenylephrine)
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Interactions between your drugs
Using dextromethorphan together with diphenhydrAMINE may increase side effects such as dizziness, drowsiness, confusion, and difficulty concentrating. Some people, especially the elderly, may also experience impairment in thinking, judgment, and motor coordination. 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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Using dextromethorphan together with doxylamine may increase side effects such as dizziness, drowsiness, confusion, and difficulty concentrating. Some people, especially the elderly, may also experience impairment in thinking, judgment, and motor coordination. 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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Using diphenhydrAMINE together with doxylamine 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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Drug and food interactions
Ask your doctor before using acetaminophen together with ethanol (alcohol). This can cause serious side effects that affect your liver. Call your doctor immediately if you experience a fever, chills, joint pain or swelling, excessive tiredness or weakness, unusual bleeding or bruising, skin rash or itching, loss of appetite, nausea, vomiting, or yellowing of the skin or the whites of your eyes. If your doctor does prescribe these medications together, you may need a dose adjustment or special tests to safely take both 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.
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Alcohol can increase the nervous system side effects of dextromethorphan 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 dextromethorphan. Do not use more than the recommended dose of dextromethorphan, 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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Alcohol can increase the nervous system side effects of doxylamine 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 doxylamine. Do not use more than the recommended dose of doxylamine, 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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Ask your doctor before using diphenhydrAMINE together with ethanol (alcohol). Use alcohol cautiously. Alcohol may increase drowsiness and dizziness while you are taking diphenhydrAMINE. You should be warned not to exceed recommended dosages and to avoid activities requiring mental alertness. If your doctor prescribes these medications together, you may need a dose adjustment to safely take this combination. 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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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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Therapeutic duplication warnings
Therapeutic duplication is the use of more than one medicine from the same drug category or therapeutic class to treat the same condition. This can be intentional in cases where drugs with similar actions are used together for demonstrated therapeutic benefit. It can also be unintentional in cases where a patient has been treated by more than one doctor, or had prescriptions filled at more than one pharmacy, and can have potentially adverse consequences.
The recommended maximum number of medicines in the 'antihistamines' category to be taken concurrently is usually one. Your list includes two medicines belonging to the 'antihistamines' category:
- Sudafed PE Nighttime Cold (acetaminophen/diphenhydramine/phenylephrine)
- Vicks NyQuil Severe Cold & Flu (acetaminophen/dextromethorphan/doxylamine/phenylephrine)
Note: In certain circumstances, the benefits of taking this combination of drugs may outweigh any risks. Always consult your healthcare provider before making changes to your medications or dosage.
The recommended maximum number of medicines in the 'decongestants' category to be taken concurrently is usually one. Your list includes two medicines belonging to the 'decongestants' category:
- Sudafed PE Nighttime Cold (acetaminophen/diphenhydramine/phenylephrine)
- Vicks NyQuil Severe Cold & Flu (acetaminophen/dextromethorphan/doxylamine/phenylephrine)
Note: In certain circumstances, the benefits of taking this combination of drugs may outweigh any risks. Always consult your healthcare provider before making changes to your medications or dosage.
The recommended maximum number of medicines in the 'sympathomimetics' category to be taken concurrently is usually one. Your list includes two medicines belonging to the 'sympathomimetics' category:
- Sudafed PE Nighttime Cold (acetaminophen/diphenhydramine/phenylephrine)
- Vicks NyQuil Severe Cold & Flu (acetaminophen/dextromethorphan/doxylamine/phenylephrine)
Note: In certain circumstances, the benefits of taking this combination of drugs may outweigh any risks. Always consult your healthcare provider before making changes to your medications or dosage.
The recommended maximum number of medicines in the 'sympathomimetic amines' category to be taken concurrently is usually one. Your list includes two medicines belonging to the 'sympathomimetic amines' category:
- Sudafed PE Nighttime Cold (acetaminophen/diphenhydramine/phenylephrine)
- Vicks NyQuil Severe Cold & Flu (acetaminophen/dextromethorphan/doxylamine/phenylephrine)
Note: In certain circumstances, the benefits of taking this combination of drugs may outweigh any risks. Always consult your healthcare provider before making changes to your medications or dosage.
The recommended maximum number of medicines in the 'acetaminophen' category to be taken concurrently is usually one. Your list includes two medicines belonging to the 'acetaminophen' category:
- Sudafed PE Nighttime Cold (acetaminophen/diphenhydramine/phenylephrine)
- Vicks NyQuil Severe Cold & Flu (acetaminophen/dextromethorphan/doxylamine/phenylephrine)
Note: In certain circumstances, the benefits of taking this combination of drugs may outweigh any risks. Always consult your healthcare provider before making changes to your medications or dosage.
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Drug Interaction Classification
| 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
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