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Drug Interactions between phenytoin and Spec-T Sore Throat / Decongestant Lozenges

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: Spec-T Sore Throat / Decongestant Lozenges (benzocaine / phenylephrine / phenylpropanolamine) and Spec-T Sore Throat / Decongestant Lozenges (benzocaine / 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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Moderate

phenytoin benzocaine topical

Applies to: phenytoin and Spec-T Sore Throat / Decongestant Lozenges (benzocaine / phenylephrine / phenylpropanolamine)

Some of the medication in benzocaine topical may be absorbed into the bloodstream following local application. When present in sufficient concentrations in the blood, local anesthetics such as benzocaine topical may cause methemoglobinemia, a rare condition that can lead to oxygen deprivation in tissues and vital organs due to reduced oxygen-carrying capacity of the blood. The risk is increased when combined with other medications that can also induce methemoglobinemia such as phenytoin. Individuals may be more susceptible to developing methemoglobinemia during treatment with these medications if they are very young (especially neonates and infants) or have anemia, diseases of the heart or lungs, blood circulation disorders, liver cirrhosis, shock, sepsis, and certain genetic predispositions such as NADH cytochrome-b5 reductase deficiency, glucose-6-phosphate dehydrogenase deficiency, and hemoglobin M. In addition, use of topical anesthetics on inflamed or abraded areas or broken skin, as well as excessive use such as application of large doses or on larger than recommended areas, can increase absorption and result in high blood levels of the medication. Topical anesthetics that are applied to mucous membranes such as inside the mouth, nose, or throat (e.G., for sore throat; for numbing prior to dental procedures or scoping of the lungs or gastrointestinal tract) may also be absorbed to a significant extent. Close medical supervision is necessary when medications that can cause methemoglobinemia are used together. Do not exceed the recommended dose or frequency and duration of use when treated with products that contain local anesthetics, including some over-the-counter preparations. Signs and symptoms of methemoglobinemia may be delayed by several hours after treatment with topical anesthetics. Patients (or their caregivers) should seek immediate medical attention if they develop a gray discoloration of the skin, mouth, or nail bed; nausea; headache; dizziness; lightheadedness; fatigue; shortness of breath; rapid or shallow breathing; a rapid heartbeat; palpitation; anxiety; or confusion. 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

phenytoin food

Applies to: phenytoin

Phenytoin levels may decrease when the suspension is given with enteral feedings. This could lead to a loss of seizure control. You could interrupt the feeding for 2 hours before and after the phenytoin dose. Alternatively, you may give the phenytoin suspension diluted in water and flush the tube with water after administration. These would make it easier for your body to absorb the medication. However, this still may not entirely avoid the interaction and may not always be feasible. You should have your phenytoin levels checked upon starting and stopping of enteral feedings. In addition, using phenytoin together with food may alter the effects of phenytoin. Contact your doctor if you experience worsening of seizure control or symptoms of toxicity, including twitching eye movements, slurred speech, loss of balance, tremor, muscle stiffness or weakness, nausea, vomiting, feeling light-headed, fainting, and slow or shallow breathing. If your doctor does prescribe these medications together, you may need a dose adjustment or special test to safely use both medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Ask your doctor before making any changes to your therapy.

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Moderate

phenylpropanolamine food

Applies to: Spec-T Sore Throat / Decongestant Lozenges (benzocaine / 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

phenylephrine food

Applies to: Spec-T Sore Throat / Decongestant Lozenges (benzocaine / 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: Spec-T Sore Throat / Decongestant Lozenges (benzocaine / 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

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.