phenytoin vs ranolazine
Side-by-side comparison of phenytoin and ranolazine. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.
major Known Drug Interaction
CYP3A Inducers Do not use ranolazine with CYP3A inducers such as rifampin, rifabutin, rifapentine, phenobarbital, phenytoin, carbamazepine, and St.
Recommendation: You should avoid taking these two medicines at the same time.
Dilantin
Ranexa
Phenytoin injection is used to treat certain types of seizures. It can also prevent seizures during or after neurosurgery.
Ranolazine extended-release tablets help treat chronic angina (chest pain). It can be used with other heart medicines.
This medicine treats generalized tonic-clonic status epilepticus, a type of prolonged seizure. It also helps prevent and treat seizures that may happen during or after brain surgery. Sometimes, it can be used for a short time instead of the oral form of phenytoin when you cannot take the medicine by mouth.
Ranolazine is used to treat chronic angina, which is chest pain that keeps coming back. It can help you have fewer angina episodes. You can take this medicine with other drugs like beta-blockers or nitrates.
Phenytoin works by slowing down the signals in the brain that cause seizures. It stabilizes nerve cell membranes, reducing excessive electrical activity. This helps to prevent seizures from starting or spreading.
Ranolazine works by affecting the sodium channels in your heart cells. This helps to improve blood flow to your heart. It reduces the amount of calcium in your heart, which can help prevent angina.
No common side effects listed.
- • Dizziness
- • Headache
- • Constipation
- • Nausea
- The medicine is reacting with another medicine 1,547
- Seizure 1,382
- Poisoning from different substances 1,353
- Convulsion 1,260
- Prolonged seizure 790
- Death 816
- Heart attack 640
- Chest pain 605
- Angina 594
- Stent placement 582
This medicine can cause serious heart problems if given too quickly. The injection rate should not be faster than 50 mg per minute for adults, and 1 to 3 mg/kg/min (or 50 mg per minute, whichever is slower) for children. Your heart will be monitored closely during and after the injection.
Ranolazine can cause changes in your heart's electrical activity (QT prolongation). If you have kidney problems, your doctor should check your kidney function. If you develop kidney failure, stop taking ranolazine.
Taking phenytoin during pregnancy may increase the risk of birth defects. If you are pregnant or plan to become pregnant, talk to your doctor about the risks and benefits of this medicine.
It is not known if ranolazine can harm an unborn baby. Talk to your doctor if you are pregnant or plan to become pregnant. It is also not known if ranolazine passes into breast milk. Discuss with your doctor if you are breastfeeding.
How to Read This phenytoin vs ranolazine Comparison
phenytoin is classified in the Anticonvulsant (Hydantoin) drug class, while ranolazine sits within the Late Sodium Current Inhibitor (Antianginal) class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are prescription-only, so a licensed provider must authorize use.
Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, phenytoin has 6,332 submissions while ranolazine has 3,237. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. These two drugs have a known major interaction flagged in FDA labeling, attributed to phenytoin makes your body clear ranolazine much faster than it should, which lowers the drug's effectiveness.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.
A table cannot substitute for clinical judgment. Effectiveness, tolerability, drug-drug interactions with your other medications, kidney and liver function, pregnancy status, insurance formulary, and price all feed into a decision that only a licensed prescriber can make responsibly. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This page is for educational purposes only, is not medical advice, and should not be used to self-switch between phenytoin and ranolazine - always consult your physician or pharmacist first.
Important: This comparison is for informational purposes only. Drug effects vary between individuals. Always consult your doctor or pharmacist for personalized medical advice.