What is WHODrug?

WHODrug is a global standardized medical dictionary developed by the World Health Organization for coding medications in clinical trials and pharmacovigilance. It is used to classify concomitant medications and treatments in a consistent manner, supporting accurate data analysis, safety evaluation, and regulatory reporting across studies and regions.

WHODrug is a global standardized dictionary used in clinical trials to code and classify medications. It is primarily used to systematically code concomitant medications that trial participants take alongside the experimental treatment. This standardization enables consistent reporting across multiple trial sites and countries, facilitates the identification of drug-drug interactions, and supports regulatory compliance. The US FDA mandates WHODrug for clinical studies, and it is widely used by pharmaceutical companies, research organizations, and regulatory authorities for medication coding and safety analysis.

Clinion embeds the WHODrug dictionary within its clinical data management processes to ensure consistent coding of medication and concomitant drug information. As data is entered, drugs are matched and coded using the most recent WHODrug versions, allowing clear identification of medicinal products, active substances, and drug groupings. The system also manages dictionary updates, re-coding activities, and audit trails, ensuring data remains consistent, traceable, and aligned with regulatory expectations throughout the clinical trial lifecycle.

The solution follows a human-in-the-loop approach, where coders can review, accept, or modify AI-suggested codes, ensuring accuracy and regulatory compliance. Because coding happens earlier and within the same workflow, Clinion helps improve data quality, reduce manual effort, and accelerate database lock and downstream analysis.

In a clinical trial, site staff enter patient medication details into the eCRF, and Clinion automatically links each entry to the appropriate WHODrug code. If a drug name is unclear or updated, data managers review and re-code it using the correct WHODrug version. All modifications are fully documented, supporting data transparency and uniform medication coding throughout the study.

As coders accept or modify these suggestions, the AI learns from those decisions, improving accuracy and consistency for similar terms over time. Routine entries move closer to auto-coding, while complex or ambiguous cases are flagged for human review reducing manual effort while keeping medical oversight firmly in place.

Medical Coding

Concomitant Medication

MedDRA

WHODrug Koda

Drug Dictionary

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