folic acid vs phenytoin

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Side-by-side comparison of folic acid and phenytoin. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.

minor Known Drug Interaction

Table 1: Drugs That Affect Phenytoin Concentrations Interacting Agent Examples Drugs that may increase phenytoin serum levels Antiepileptic drugs Ethosuximide, felbamate, oxcarbazepine, methsuximide, topiramate Azoles Fluconazole, ketoconazole, itraconazole, miconazole, voriconazole Antineoplastic agents Capecitabine, fluorouracil Antidepressants Fluoxetine, fluvoxamine, sertraline Gastric acid reducing agents H 2 antagonists (cimetidine), omeprazole Sulfonamides Sulfamethizole, sulfaphenazole, sulfadiazine, sulfamethoxazole trimethoprim Other Acute alcohol intake, amiodarone,...

Drug Class
folic acid B Vitamin (Folate) Supplement
phenytoin Anticonvulsant (Hydantoin)
Type
folic acid Over-the-Counter
phenytoin Prescription
Summary
folic acid

Integra FTM is a medicine that helps treat iron and folate deficiencies. It is also used during pregnancy to prevent and treat iron deficiency and provide folic acid.

phenytoin

Phenytoin injection is used to treat certain types of seizures. It can also prevent seizures during or after neurosurgery.

What It Treats
folic acid

Integra FTM treats iron deficiency anemia and folate deficiency anemia. It is also used during pregnancy to prevent and treat iron deficiency. This medicine also provides a maintenance dosage of folic acid during pregnancy.

phenytoin

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.

How It Works
folic acid

Integra FTM contains two types of iron that your body can use. These iron types help to increase the amount of iron in your blood. Folic acid is a B vitamin that helps your body make new blood cells.

phenytoin

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.

Common Side Effects
folic acid
  • Upset stomach
  • Nausea
  • Diarrhea
  • Constipation
  • Heartburn
phenytoin

No common side effects listed.

FAERS Reports
folic acid
  • Fatigue 23,332
  • Pain 23,054
  • Arthralgia 19,495
  • Rheumatoid Arthritis 17,528
  • Nausea 15,633
phenytoin
  • Drug Interaction 1,547
  • Seizure 1,382
  • Toxicity To Various Agents 1,353
  • Convulsion 1,262
  • Status Epilepticus 791
Serious Warnings
folic acid

Accidental overdose of iron-containing products is a leading cause of fatal poisoning in young children. Keep this medicine away from children. If someone overdoses, call a doctor or poison control center right away. Folic acid alone is not the right treatment for pernicious anemia or other megaloblastic anemias where Vitamin B12 is lacking.

phenytoin

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.

Pregnancy
folic acid

Integra FTM can be used during pregnancy to prevent and treat iron deficiency and to provide folic acid. Talk to your doctor before taking this medicine if you are pregnant or breastfeeding.

phenytoin

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.

How to Read This folic acid vs phenytoin Comparison

folic acid is classified in the B Vitamin (Folate) Supplement drug class, while phenytoin sits within the Anticonvulsant (Hydantoin) class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are split between OTC and prescription status, which affects access and supervision.

Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, folic acid has 99,042 submissions while phenytoin has 6,335. 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 minor interaction flagged in FDA labeling, attributed to taking these two together can cause the levels of both drugs in your blood to drop, making them both less effective.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.

A table cannot represent individual circumstances. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This registry does not provide medical, treatment, substitution, or medication-change directions for folic acid or phenytoin.

Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.