Smarter Workflows: Automating Medication Refills with AI and n8n

Reading Time: 10 min ⏱️

Introduction

In today's rapidly evolving business landscape, secure and efficient user authentication isn't merely a technical requirement—it's a critical business differentiator. This article demonstrates building an enterprise-grade application that leverages Microsoft Entra External ID for frictionless customer onboarding and authentication while integrating with n8n to orchestrate sophisticated backend workflows.

We'll examine how Microsoft Entra External ID delivers enterprise-level identity management, and how pairing it with n8n's powerful workflow automation creates measurable operational efficiencies. Our business case study: a medication refill automation solution that enhances customer experience through secure verification, employs OpenAI GPT-5 for intelligent data processing, and provides real-time analytics via Google Sheets integration—driving both cost reduction and improved service delivery.

What is Microsoft Entra External ID?

Microsoft Entra External ID is an identity and access management (IAM) service designed to authenticate external users—partners, suppliers, patients, or customers—without needing them to be part of your internal directory.

Key capabilities include:

• Customizable sign-up and sign-in experiences.

• Integration with OAuth2 / OpenID Connect protocols for secure access.

• Support for external identities like B2B partners or application end-users.

For developers, it means you can authenticate and authorize users in your apps while maintaining compliance and minimizing security risks.

Microsoft Graph and Its Role with Microsoft Entra

While Microsoft Entra External ID provides the authentication and authorization framework, the actual user data that applications depend on—such as profile attributes, custom fields, and directory information—comes through Microsoft Graph.

Microsoft Graph is Microsoft’s unified API endpoint that allows developers to securely access data across Microsoft 365 and Azure Active Directory (now Entra ID). For applications built on Entra External ID, Graph acts as the bridge between authentication and actionable identity data.

How it fits together in our solution:

• Authentication via Entra External ID: Patients first sign in using secure OAuth2/OpenID Connect flows managed by Entra.

• Profile retrieval via Microsoft Graph: Once authenticated, the app exchanges the access token for profile information using the Graph API. In our medication refill use case, we pull attributes like:

  • displayName and mail (for user identity)

  • Custom attributes such as DateOfBirth, HospitalNumber, and Gender (extensions stored in Entra).

• Integration with n8n: The verified data flows into the n8n workflow, ensuring that downstream steps—like GPT-5 classification and Google Sheets logging—are anchored to validated patient information.

This dual use of Entra and Graph ensures that the system not only authenticates who the user is but also provides the contextual identity data needed to drive automation securely and accurately.

Benefits of Using Entra External ID for Seamless Sign-In

When building a public-facing business or healthcare app, Entra External ID offers:

• Strong security: OAuth2 + OpenID Connect reduce exposure to password-related attacks.

• Consistent experience: Users enjoy a familiar and branded login flow.

• Attribute access: Retrieve and verify profile data (e.g., DOB, hospital number) directly from the identity provider.

• Scalability: Support thousands of external accounts without managing user credentials internally.

What is n8n?

n8n is an open-source workflow automation platform that allows you to create custom workflows by connecting different apps, services, and systems without extensive coding knowledge. The name stands for "node-based no-code," reflecting its visual approach to automation.

How n8n Works

n8n operates using a visual node-based architecture where each action or service is represented as a node. You create workflows by connecting these nodes together like puzzle pieces, where data flows from one node to another as arrays of JSON objects called "items". The platform provides a browser-based visual interface that makes workflow creation accessible to both technical and non-technical users.

A typical workflow consists of:

• Trigger nodes: Events that start your workflow (like new form submissions, emails, or API events)

• Action nodes: Specific tasks performed in the workflow (sending emails, updating databases, generating AI responses)

Key Features and Capabilities

n8n offers several distinctive advantages:

• Hybrid approach: Combines visual drag-and-drop interface with the ability to write custom JavaScript or Python code when needed

• Self-hosting options: Available as a completely free self-hosted solution or cloud-hosted plans starting at €20/month

• Extensive integrations: Connects with over 350 applications and offers 1,700+ pre-built templates

• AI capabilities: Incorporates AI features through LangChain integration and multi-step AI agents

Benefits of n8n

n8n is an open-source workflow automation platform that connects services and APIs with ease.

Advantages for this project include:

• Visual workflow building: Drag-and-drop nodes for APIs, AI models, and databases.

• No heavy coding: Complex logic without building backend from scratch.

• Extensive integrations: Microsoft Graph API, Google Sheets, OpenAI, and more.

• Scalable automation: Handle both small and enterprise-scale tasks.

Use Case: Medication Refill Automation Application

This section provides a comprehensive, step-by-step walkthrough of building a sophisticated Medication Refill Automation system that leverages multiple technologies: Microsoft Entra External ID for secure patient authentication, n8n for streamlined workflow automation, the advanced OpenAI GPT-5 Model for intelligent medication classification, and Google Sheets for efficient data storage and retrieval. We'll explore each component in detail, showing exactly how they integrate to create a seamless patient experience while maintaining security and compliance standards.

The challenge: Patients often need to request prescription refills via multiple channels—phone, in-person, or web. These processes can be slow and prone to errors if patient identity isn't verified.

The solution: A Flask web app with:

• Login via Microsoft Entra External ID (app.py).

• Refill form that captures Date of Birth (DOB), Hospital Number (HN), and Medication details (form.html).

• Automated backend workflow in n8n to:

  1. Receive the form submission via webhook.

  2. Verify patient profile from Microsoft Graph API (DOB, HN, Gender).

  3. Edit Fields to normalize and clean the patient data.

  4. Classify medication using GPT-5 (extract generic name, strength, form, use type, therapeutic class, and controlled substance status).

  5. Extract GPT JSON String to parse the structured response from OpenAI.

  6. Merge verification and classification results into a single data row.

  7. Build Final Row to format data for Google Sheets integration.

  8. Add to Google Sheets log the request into a Google Sheets dashboard for pharmacist review.

Sample logged data:

Step-by-Step Implementation Walkthrough

More n8n Use Case Ideas Across Business Functions

Beyond medication refills, the same architecture can be adapted to:

• Healthcare: Automating appointment bookings, patient surveys, or lab result notifications.

• Retail: Streamlined vendor onboarding with identity verification.

• Finance: Loan application pre-screening with secure sign-in and document checks.

• Education: Course enrollment verification for external students.

• Events: Attendee check-in with instant credential verification.

Conclusion

By combining Microsoft Entra External ID for authentication and n8n for process automation, businesses can create secure, scalable, and highly integrated applications. Our medication refill use case demonstrates how this approach reduces manual verification work, improves accuracy, and enhances the user experience.

Whether in healthcare or any other industry, the pattern is clear: secure identity + smart automation = productivity gains and happier users.

Where to Go Next

For further exploration, consider these helpful resources:

Microsoft Learn:

• Guided project – Build a sample app to evaluate Microsoft Entra External ID for seamless and secure sign-up and sign-in for consumers and business customers

• Test your sign-up and sign-in user flow

• Add user attributes to token claims

n8n:

• Using n8n

• Integrations

• Hosting n8n

• Code in n8n

• Advanced AI

• API

OpenAI:

• Using GPT-5

• New API features in GPT-5

• Migrating from other models to GPT-5

• Prompting best practices for GPT-5

Google Cloud:

• Create a Google Cloud Project to Get Started

• Setup Authentication

• Manage Credentials for APIs

• Google Sheets API Overview