What Is Phenytoin Used For? FDA-Approved Uses

The FDA label says: “Extended phenytoin sodium capsules are indicated for the treatment of tonic-clonic (grand mal) and psychomotor (temporal lobe) seizures and prevention and treatment of seizures occurring during or following neurosurgery.”

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Phenytoin Sodium, capsule, extended release

Indications and Usage, quoted from the label by Sun Pharmaceutical Industries, Inc. (ANDA040684). Cross-references to other label sections are left out.

Extended phenytoin sodium capsules are indicated for the treatment of tonic-clonic (grand mal) and psychomotor (temporal lobe) seizures and prevention and treatment of seizures occurring during or following neurosurgery.

Source: DailyMed label, set id 601f7353-225d-4a5d-9810-3869c2c21874, version 16, effective March 17, 2026. NDC 51672-4111, one of 21 listings for this product.

Phenytoin Sodium, injection

Indications and Usage, quoted from the label by Acella Pharmaceuticals, LLC (ANDA040573). Cross-references to other label sections are left out.

Parenteral Phenytoin Sodium Injection is indicated for the treatment of generalized tonic-clonic status epilepticus, and prevention and treatment of seizures occurring during neurosurgery. Intravenous Phenytoin Sodium Injection can also be substituted, as short-term use, for oral phenytoin. Parenteral Phenytoin should be used only when oral phenytoin administration is not possible.

Source: DailyMed label, set id 6922f32f-8bed-4c09-8103-27987bcbd104, version 7, effective September 16, 2024. NDC 42192-614, one of 11 listings for this product.

Phenytoin, tablet, chewable

Indications and Usage, quoted from the label by Parke-Davis Div of Pfizer Inc (ANDA084427). Cross-references to other label sections are left out.

DILANTIN INFATABS are indicated for the treatment of generalized tonic-clonic (grand mal) and complex partial (psychomotor, temporal lobe) seizures and prevention and treatment of seizures occurring during or following neurosurgery.

Source: DailyMed label, set id ca119a89-2394-4d34-8078-cd1fa4e8e2f1, version 58, effective May 12, 2026. NDC 0071-0007, one of 9 listings for this product.

Questions

What is phenytoin used for?

The FDA label says: “Extended phenytoin sodium capsules are indicated for the treatment of tonic-clonic (grand mal) and psychomotor (temporal lobe) seizures and prevention and treatment of seizures occurring during or following neurosurgery.”

What drug class is phenytoin?

FDA lists phenytoin in the Anti-epileptic Agent established pharmacologic class.

Does this page cover off-label uses or dosing?

No. This page shows only the Indications and Usage section of the FDA label. Ask a pharmacist or prescriber about dosing.