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Hydroxyurea 100 MG Oral Tablet [Siklos] — RxCUI 1999314

RxNorm drug concept · Semantic branded drug
RxCUI 1999314 Semantic branded drug · SBD ● Current RxNorm concept 2 FDA products 2 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

RxCUI1999314
Official nameHydroxyurea 100 MG Oral Tablet [Siklos]
Concept typeSemantic branded drug (SBD)
RxNorm statusCurrent RxNorm concept
Also known asSiklos 100 MG Oral Tablet
FDA products mapped2
Package NDCs mapped2
Reported Medicaid activity (SDUD)8,692 prescriptions · 25 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 Hydroxyurea: what it is, how it’s used, side effects, and interactions.

📗 Our plain-language guide HelloPharmacist
  • It's actually both, depending on the specific product. Droxia, Siklos, and Xromi are each approved to reduce the painful crises and blood transfusion needs in sickle cell anemia. H...
  • What exactly is hydroxyurea used for — is it a cancer drug or a sickle cell drug?
  • Very regularly — typically every two weeks while your dose is being adjusted. Hydroxyurea can lower your white blood cell and platelet counts, so monitoring is built into the treat...
  • How often will I need blood tests while I'm on this medication?
📖 Read our full Hydroxyurea guide →

🕸️ Concept Web — How Hydroxyurea 100 MG Oral Tablet [Siklos] 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 Hydroxyurea 100 MG Oral Tablet [Siklos] RxCUI 1999314

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.

    • Hydroxyurea 5552
  2. Brand names 1

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

    • Siklos 1999309
  3. Dose forms 9

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

    • Hydroxyurea Oral Tablet 370657
    • Hydroxyurea Oral Product 1160113
    • Hydroxyurea Pill 1160114
    • Hydroxyurea Oral Tablet [Siklos] 1999311
    • Siklos Oral Product 1999312
    • Siklos Pill 1999313
    • 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

  • Hydroxyurea 100 MG Oral Tablet SCD · 1999308
  • Hydroxyurea 100 MG SCDC · 1999307
  • Hydroxyurea Oral Tablet SCDF · 370657
  • Hydroxyurea Oral Product SCDG · 1160113
  • Hydroxyurea Pill SCDG · 1160114

Brand-Name Concepts

  • Hydroxyurea 100 MG [Siklos] SBDC · 1999310
  • Hydroxyurea Oral Tablet [Siklos] SBDF · 1999311
  • Siklos Oral Product SBDG · 1999312
  • Siklos Pill SBDG · 1999313
  • Siklos BN · 1999309

📦 FDA Products & Package NDCs

2 products · 2 package NDCs
2 package NDCs map to RxCUI 1999314 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
71770-0105-60 1 BOTTLE in 1 CARTON (71770-105-60) / 60 TABLET, FILM COATE... Siklos Medunik 2020-10-15
71770-0120-30 1 BOTTLE in 1 CARTON (71770-120-30) / 30 TABLET, FILM COATE... Siklos Medunik 2018-04-15
Observed labelers: Medunik (2) — 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.