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Drug Interaction Report

16 potential interactions and/or warnings found for the following 2 drugs:

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Interactions between your drugs

Moderate

theophylline phenylephrine

Applies to: Hydroxy Compound (ephedrine / hydroxyzine / theophylline), Altex Liquid (guaifenesin / phenylephrine / phenylpropanolamine)

Both theophylline and phenylephrine 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

theophylline phenylpropanolamine

Applies to: Hydroxy Compound (ephedrine / hydroxyzine / theophylline), Altex Liquid (guaifenesin / phenylephrine / phenylpropanolamine)

Both theophylline 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

ePHEDrine phenylephrine

Applies to: Hydroxy Compound (ephedrine / hydroxyzine / theophylline), Altex Liquid (guaifenesin / phenylephrine / phenylpropanolamine)

Both ePHEDrine and phenylephrine 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

ePHEDrine phenylpropanolamine

Applies to: Hydroxy Compound (ephedrine / hydroxyzine / theophylline), Altex Liquid (guaifenesin / phenylephrine / phenylpropanolamine)

Both ePHEDrine 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

phenylephrine phenylpropanolamine

Applies to: Altex Liquid (guaifenesin / phenylephrine / phenylpropanolamine), Altex Liquid (guaifenesin / phenylephrine / phenylpropanolamine)

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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Minor

theophylline ePHEDrine

Applies to: Hydroxy Compound (ephedrine / hydroxyzine / theophylline), Hydroxy Compound (ephedrine / hydroxyzine / theophylline)

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

Drug and food interactions

Moderate

theophylline food

Applies to: Hydroxy Compound (ephedrine / hydroxyzine / theophylline)

Both smoking and excessive caffeine consumption can alter the blood levels of theophylline, which may affect the dosing. Tobacco and marijuana smoke (including secondhand exposure) generally reduces, while caffeine increases, blood levels. In addition, caffeine is a stimulant and may add to the side effects of theophylline such as headache, insomnia, and increases in blood pressure and heart rate. It is best to avoid smoking and to limit caffeine consumption during theophylline therapy. Talk to a healthcare professional if you have any questions or concerns. If you start smoking or undergo smoking cessation, your doctor may need to monitor your blood levels more closely to determine if you need a dose adjustment of theophylline. You should stop taking theophylline and seek medical attention if you experience potential signs and symptoms of excessive drug levels such as nausea, vomiting, persistent headache, insomnia, and rapid 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.



When theophylline is given with enteral (tube) feedings, blood levels may be decreased due to interference with its absorption. This may reduce the effectiveness of the medication. To minimize potential for interaction, you may interrupt the feeding for one hour before and one hour after the theophylline dose. You may need more frequent blood tests to monitor theophylline levels.

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Moderate

phenylpropanolamine food

Applies to: Altex Liquid (guaifenesin / phenylephrine / phenylpropanolamine)

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

hydrOXYzine food

Applies to: Hydroxy Compound (ephedrine / hydroxyzine / theophylline)

Alcohol can increase the nervous system side effects of hydrOXYzine 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 hydrOXYzine. Do not use more than the recommended dose of hydrOXYzine, 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

theophylline food

Applies to: Hydroxy Compound (ephedrine / hydroxyzine / theophylline)

Ask your doctor before using theophylline together with caffeine. Using these medications together may increase some of the side effects of theophylline. This can cause nausea, vomiting, insomnia, tremors, restlessness, uneven heartbeats, and seizure (convulsions). Avoid drinks or foods that contain caffeine, such as coffee, tea, cola, and chocolate. You may need a dose adjustment or special test if you use 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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Moderate

ePHEDrine food

Applies to: Hydroxy Compound (ephedrine / hydroxyzine / theophylline)

Both ePHEDrine 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

phenylephrine food

Applies to: Altex Liquid (guaifenesin / phenylephrine / phenylpropanolamine)

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: Altex Liquid (guaifenesin / phenylephrine / phenylpropanolamine)

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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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.

Duplication

Decongestants

Therapeutic duplication

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:

  • Altex Liquid (guaifenesin / phenylephrine / phenylpropanolamine)
  • Hydroxy Compound (ephedrine / hydroxyzine / theophylline)

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.

Duplication

Sympathomimetics

Therapeutic duplication

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:

  • Altex Liquid (guaifenesin / phenylephrine / phenylpropanolamine)
  • Hydroxy Compound (ephedrine / hydroxyzine / theophylline)

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.

Duplication

Sympathomimetic amines

Therapeutic duplication

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:

  • Altex Liquid (guaifenesin / phenylephrine / phenylpropanolamine)
  • Hydroxy Compound (ephedrine / hydroxyzine / theophylline)

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

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.