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Rifaximin 550 MG Oral Tablet [XIFAXAN] — RxCUI 856666

RxNorm drug concept · Semantic branded drug
RxCUI 856666 Semantic branded drug · SBD ● Current RxNorm concept 3 FDA products 6 package NDCs Snapshot Jul 14, 2026

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Compiled from public NLM RxNorm and FDA (openFDA NDC directory) data sources. Editorial policy

What you’re looking at: the standardized identity of one medicine, as the U.S. drug-data system sees it. Below — every FDA-listed product, package code, price benchmark, and billing code that maps to it.

🗂️ Key Facts

RxCUI856666
Official nameRifaximin 550 MG Oral Tablet [XIFAXAN]
Concept typeSemantic branded drug (SBD)
RxNorm statusCurrent RxNorm concept
Also known asXifaxan 550 MG Oral Tablet
FDA products mapped3
Package NDCs mapped6
Reported Medicaid activity (SDUD)118,294 prescriptions · 52 state & territory Medicaid programs · latest period Q4 2025
RxNorm release07/06/2026
Snapshot dataJul 14, 2026

📖 Skip the Codes — Read It in Plain English.

Our pharmacist-built guide to Rifaximin: what it is, how it’s used, side effects, and interactions.

📗 Our plain-language guide HelloPharmacist
  • Xifaxan has three approved uses. It treats travelers' diarrhea caused by a specific bacteria called E. coli — the kind of diarrhea you might pick up on an international trip. It al...
  • You can take Xifaxan with or without food — whichever is easier for you. What really matters is sticking to the schedule your doctor gave you. The number of times per day and the l...
  • Can I take Xifaxan with food, and does it matter when I take it?
  • If your symptoms aren't improving or are getting worse after 24 to 48 hours, stop taking Xifaxan and call your doctor. Xifaxan only works for a specific type of travelers' diarrhea...
📖 Read our full Rifaximin guide →

🕸️ Concept Web — How Rifaximin 550 MG Oral Tablet [XIFAXAN] Connects

One RxCUI never lives alone. Follow the path from the raw ingredient down to the exact strength-and-form concepts FDA products carry — every stop is a real RxNorm concept with its own identifier. Hover or focus any chip for what it means.
This page's concept Rifaximin 550 MG Oral Tablet [XIFAXAN] RxCUI 856666

Every web starts here: one RxCUI, one fixed meaning in the RxNorm vocabulary.

  1. Ingredients 1

    The active substance itself — no strength, form, or brand attached yet.

    • Rifaximin 35619
  2. Brand names 1

    The same medicine's trade names. A brand name alone says nothing about strength or form.

    • XIFAXAN 539786
  3. Dose forms 9

    The ingredient poured into a form — tablet, solution, cream — still without one fixed strength.

    • Rifaximin Oral Tablet 451309
    • Rifaximin Oral Product 1157434
    • Rifaximin Pill 1157435
    • Rifaximin Oral Tablet [XIFAXAN] 539788
    • XIFAXAN Oral Product 1186266
    • XIFAXAN Pill 1186267
    • Oral Tablet 317541
    • Oral Product 1151131
    • +1 more in this family
  4. Clinical & branded drugs 3

    Ingredient + strength + dose form. These are the concepts real FDA products actually carry.

Showing up to 8 concepts per family — 13 of 14 stored related concepts drawn.
These are official RxNorm vocabulary relationships — how concepts name and organize the same medicine. They do not establish therapeutic equivalence or substitutability: two concepts appearing in one web is never a statement that products can be swapped.

🔀 Generic ⇄ Brand Crosswalk

The same medicine has an unbranded (generic) identity and one or more brand-name identities — each with its own RxCUI. This is a naming relationship in RxNorm, not a statement that any two products are substitutable.

Generic (Clinical) Concepts

  • Rifaximin 550 MG Oral Tablet SCD · 856664
  • Rifaximin 550 MG SCDC · 856663
  • Rifaximin Oral Tablet SCDF · 451309
  • Rifaximin Oral Product SCDG · 1157434
  • Rifaximin Pill SCDG · 1157435

Brand-Name Concepts

  • Rifaximin 550 MG [XIFAXAN] SBDC · 856665
  • Rifaximin Oral Tablet [XIFAXAN] SBDF · 539788
  • XIFAXAN Oral Product SBDG · 1186266
  • XIFAXAN Pill SBDG · 1186267
  • XIFAXAN BN · 539786

📦 FDA Products & Package NDCs

3 products · 6 package NDCs
6 package NDCs map to RxCUI 856666 in the current snapshot — up to 50 per page. Each linked NDC opens its full package page.
Package NDC Package Brand / generic name Labeler Marketing start
55154-6777-08 360 TABLET in 1 BOTTLE, PLASTIC (55154-6777-8) XIFAXAN Cardinal Health 107, LLC 2010-05-01
65649-0301-03 30 TABLET in 1 BOTTLE (65649-301-03) XIFAXAN Salix Pharmaceuticals, Inc. 2004-07-25
65649-0303-01 3 CARTON in 1 TRAY (65649-303-01) / 1 BLISTER PACK in 1 CAR... XIFAXAN Salix Pharmaceuticals, Inc. 2010-05-01
65649-0303-02 60 TABLET in 1 BOTTLE (65649-303-02) XIFAXAN Salix Pharmaceuticals, Inc. 2010-05-01
65649-0303-03 6 BLISTER PACK in 1 CARTON (65649-303-03) / 10 TABLET in 1... XIFAXAN Salix Pharmaceuticals, Inc. 2010-05-01
65649-0303-05 3 CARTON in 1 TRAY (65649-303-05) / 1 BLISTER PACK in 1 CAR... XIFAXAN Salix Pharmaceuticals, Inc. 2010-05-01
Observed labelers: Salix Pharmaceuticals, Inc. (5) · Cardinal Health 107, LLC (1) — this is the FDA-listed mapping footprint, not sales, inventory, availability, or market share.

🗃️ Sources & Limits

Atlas generation902fddb9-e9c1-4004-bf4c-dba4d51037c7
openFDA export observedJul 14, 2026
RxNorm release07/06/2026
Methodology2026-07-full-catalog-v1
  • A shared RxCUI does not prove interchangeability. Products mapped to the same concept are not thereby equivalent or substitutable — equivalence is a separate, product-level determination.
  • Listing here does not establish approval or coverage. Appearing in this snapshot is a data observation, not an FDA approval status or a payer coverage decision.
  • Missing data never means zero. A silent dataset (no price, no billing code, no utilization) means no observation — not that the real-world value is zero.
  • Counts describe the mapping footprint. Product, package, and labeler counts are the FDA-listed mapping footprint in this snapshot — not sales, inventory, availability, or market share.
This product uses publicly available data from the U.S. National Library of Medicine (NLM), National Institutes of Health, Department of Health and Human Services; NLM is not responsible for the product and does not endorse or recommend this or any other product.

Machine-readable JSON

Reference information about drug-concept identifiers and public regulatory data — not medical advice. Talk to your pharmacist or prescriber about your own medication.