Live data · NADAC + Part D CY24 · reviewed daily

Primidone (Mysoline)

Anti-epileptic Agent class · 7 generic manufacturers · 14 ANDAs filed at FDA.

First FDA approval1978-12-01
Generic availableYes · 7 mfrs
Shortage statusNone
340B exposureunknown
Last updated
NADAC: weekly (every Wed)Part D Formulary: quarterlyPart D Spend: annual (CY24)Orange Book: weeklyShortages: daily
At a glance · the numbers a plan sponsor wants on screen one

$70.7M in CY2024 Part D spend2.2M claims · 564K beneficiaries · 329 plans surveyed

Lowest NADAC
$0.091/unit
20 NDCs benchmarked, lowest of all strengths.
Average NADAC
$0.112
Across all dosage forms in distribution.
Highest NADAC
$0.228
Range is tight.
Plans with PA
0 / 329
Zero PA friction across surveyed plans.

Questions a plan sponsor actually asks.

FAQPage schema10 entries indexed · 4 visible
What is Primidone used for?

Primidone is tracked in Medicare Part D. Specific indication information is not available in our current dataset.

Sources: CMS Part D Spending CY24 · CMS NADAC weekly · FDA Orange Book
Is there a generic for Primidone?

Yes. 14 ANDAs filed at FDA, 7 generic manufacturers currently shipping.

Sources: CMS Part D Spending CY24 · CMS NADAC weekly · FDA Orange Book
How much does my plan pay for Primidone?

Across 329 Part D plans, Primidone averages $0.112/unit (NADAC). Lowest available: $0.091/unit. Highest in distribution: $0.228/unit.

Sources: CMS Part D Spending CY24 · CMS NADAC weekly · FDA Orange Book
Is Primidone on the FDA shortage list?

No. Primidone is not currently on the FDA Drug Shortage Database.

Sources: CMS Part D Spending CY24 · CMS NADAC weekly · FDA Orange Book

6 additional drug-specific questions are indexed in the page's FAQPage schema for search engines and LLM crawlers, beyond what renders visually above. View page source for the complete JSON-LD.

Related questions.

Q&A librarySourced · reviewed quarterly
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Sources · every number above traces back.

Last refresh15 Oct 2026

Drug identity, dosage forms, brand names: openFDA NDC Directory · First approval, ANDA history: FDA Orange Book (10 approvals on file) · NADAC unit costs: CMS NADAC weekly file (20 NDCs benchmarked) · Formulary tier and PA placement: CMS Part D Formulary file (329 plans) · Annualized spend, claims, beneficiaries: CMS Part D Spending Dashboard (CY2024) · Shortage status: FDA Drug Shortage Database · 340B exposure: HRSA OPAIS. Methodology and reproducibility notes on /methodology.