Drug Interactions between benoxinate / fluorescein ophthalmic and phenytoin
This report displays the potential drug interactions for the following 2 drugs:
- benoxinate/fluorescein ophthalmic
Interactions between your drugs
phenytoin benoxinate ophthalmic
Applies to: phenytoin and benoxinate / fluorescein ophthalmic
Some of the medication in benoxinate ophthalmic may be absorbed into the bloodstream following local application. When present in sufficient concentrations in the blood, local anesthetics such as benoxinate ophthalmic 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.
Drug and food interactions
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.
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.
Drug Interaction Classification
|Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.|
|Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.|
|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.|
|No interaction information available.|
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.