Rifampin vs Rifaximin — Cost, Coverage & Plan Comparison

Pick the drugs you want to compare.

Up to 4 drugsCross-class or same-class

Start with the molecules your plan spends the most on. Most useful comparisons live within the same therapeutic class — switching across classes requires deeper clinical review.

Drug 1

Drug 2

Drug 3 (optional)

Drug 4 (optional)

Side by side, line by line.

Federal data onlyNo PBM pricing assumed

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11 dimensions

Rifamycin Antibacterial

Rifampin

Brand: Rifadin IV

First FDA approval: 1989-05-25

Rifamycin Antibacterial

Rifaximin

Brand: XIFAXAN

First FDA approval: 2004-07-25

Lowest NADACAcquisition cost floor across all NDCs

$0.625Per unit

—Per unit

Average NADACAcross all dosage forms and strengths

$0.665Up to $0.686

—

Generic manufacturersActive ANDA holders — FDA Orange Book

711 total ANDAs filed

00 total ANDAs filed

Annualized Part D spendCY2024 — CMS Part D Spending Dashboard

$10.7MFull year

$1.80BFull year

Part D claims (CY24)Total fills, all strengths

167K64K beneficiaries

637K179K beneficiaries

Avg cost per claimCalculated: total spend ÷ total claims

$64Per claim, all NDCs

$2,822Per claim, all NDCs

Part D plans surveyed2026 plan year — CMS Formulary file

329Across CMS plan year

Prior-authorization frictionPlan-NDC pairs requiring PA

2Minimal friction

470Substantial friction

Step therapy appliedPlan-NDC pairs requiring step therapy

0None

FDA shortage statusLive cross-reference vs FDA Drug Shortage Database

Active shortageSee drug profile

NoneClear

Generic availableFDA Orange Book

Yes7 manufacturers

NoBrand-only