Frequently Asked Questions

RxLabelGuard is designed around FDA Structured Product Labeling (SPL) data delivered through openFDA and DailyMed endpoints.

These sources expose labeling sections such as warnings, contraindications, and drug interactions that are required in regulated labeling formats.

A drug interaction API is a programmatic interface that accepts drug names or identifiers and returns structured data about known interactions between those drugs. This typically includes severity levels, mechanisms of action, clinical recommendations, and source references.

Drug interaction APIs are used by EHR systems, pharmacy software, clinical decision support tools, and telehealth platforms to surface safety alerts during prescribing, dispensing, or medication reconciliation workflows.

RxLabelGuard provides a REST API that sources interaction data from FDA Structured Product Labeling, returning severity-scored results with evidence citations for each interaction pair.

To check drug interactions programmatically, you send a list of drug names to an API endpoint and receive structured interaction data in the response. With RxLabelGuard, you POST to /v1/interactions/check with a JSON body containing a drugs array.

The API resolves each drug name to a stable identifier (RxCUI) via RxNorm, fetches the corresponding FDA label, extracts interaction statements, and returns structured pairs with severity levels, mechanisms, recommendations, and evidence citations.

Most teams integrate this into their medication entry or prescribing workflows, calling the API whenever a new drug is added to a patient's medication list.

openFDA provides high-value structured/searchable access to labeling data, including interaction-related sections.

Most product teams still add a normalization layer to convert label text into consistent severity classes, recommendation statements, and audit-friendly outputs.

RxLabelGuard classifies drug interactions into five severity levels: contraindicated (must not be used together), major (potentially life-threatening, requires clinical intervention), moderate (may require monitoring or dosage adjustment), minor (minimal clinical significance), and unknown (insufficient data to classify).

Severity is determined by analyzing the language and context of the FDA label's drug interaction section, including keywords related to clinical risk, monitoring requirements, and contraindication statements.

Each interaction result includes the severity level alongside the mechanism of action, clinical recommendation, and an evidence snippet from the source FDA label for verification.

DailyMed is an official NLM channel for SPL documents and provides web services and downloadable resources for obtaining label content.

In practice, many teams combine DailyMed/openFDA ingestion with custom parsers and normalization logic for app-ready APIs.

RxNorm and RxNav APIs focus on normalized medication concepts and ID mapping, which helps reconcile free-text drug inputs to consistent identifiers.

That normalization layer reduces ambiguity before interaction rules or extracted evidence are applied.

Structured Product Labeling (SPL) is the FDA's required format for submitting drug labeling content electronically. It uses an XML-based standard that tags each section of a drug label — including drug interactions, warnings, contraindications, and boxed warnings — with machine-readable identifiers.

SPL data is the foundation for both openFDA and DailyMed. When a manufacturer submits or updates a drug label, the SPL content flows into these public systems, making it available for programmatic access.

For drug interaction APIs, the key SPL sections are Section 7 (Drug Interactions) and related safety sections. These contain the narrative text that describes known interaction risks, mechanisms, and clinical recommendations.

Yes. RxLabelGuard offers a free Sandbox tier that includes 50 API requests per month and 1 API key. This is designed for exploration, prototyping, and initial integration testing.

The Developer tier at $20/month provides 2,000 requests per month with 5 API keys and all response formats. The Professional tier at $99/month includes 20,000 requests per month with unlimited API keys and a 99.5% uptime SLA.

You can create a free account and start making API requests without providing a credit card.

EHR integration typically involves calling the RxLabelGuard API during the medication ordering or prescribing workflow. When a clinician adds a new medication, your system sends the full medication list to the /v1/interactions/check endpoint and displays any flagged interactions in the clinical interface.

The API returns structured JSON with severity levels and recommendations, which can be mapped to your EHR's alert system. Most teams display contraindicated and major interactions as hard stops or prominent warnings, while moderate and minor interactions appear as informational alerts.

RxLabelGuard's evidence citations (SPL Set ID, label section, evidence snippet) support audit trail requirements that are common in clinical software certifications.

No. The NLM Drug-Drug Interaction API, which was part of the RxNav API family, was discontinued in January 2024. Teams that relied on this endpoint for interaction checking need an alternative data source and extraction pipeline.

RxNorm and the other RxNav APIs (for drug name normalization, RxCUI lookups, and concept mapping) remain active and available. The discontinuation only affected the interaction-specific endpoints.

RxLabelGuard was designed with this gap in mind — it combines RxNorm normalization (still active) with FDA label evidence extraction to provide a complete interaction detection pipeline.

Commercial providers can package drug intelligence as managed APIs, but access and usage are typically governed by paid licensing and terms.

Open public sources remain critical for transparency and traceability, especially where teams need source-level verification.

Every interaction returned by RxLabelGuard includes an evidence citation linking back to the FDA source label. This includes the SPL Set ID (a stable identifier for the label), the specific label section where the interaction was found (e.g., drug_interactions, warnings), and an evidence snippet showing the relevant text.

These citations allow downstream systems to verify the interaction claim against the original FDA label, which is important for clinical governance, quality assurance, and regulatory compliance workflows.

You can use the SPL Set ID to link directly to the corresponding label on DailyMed for full-text review.

RxLabelGuard supports three response formats: structured (default), summary, and conversational. The structured format returns full JSON with drug resolutions, interaction pairs, severity data, and evidence citations.

The summary format adds a concise AI-generated bullet-point summary alongside the structured data. The conversational format adds a natural-language explanation suitable for patient-facing or clinical communication contexts.

All formats include the same underlying structured data — the format parameter controls whether an additional AI-generated text layer is included in the response.

RxLabelGuard processes drug names, not patient data. The API accepts a list of drug names or identifiers and returns interaction data. No protected health information (PHI) is required in API requests or stored on RxLabelGuard servers.

Because the API operates at the drug level rather than the patient level, the primary HIPAA considerations are on your side — ensuring that your application does not send PHI in API request metadata (such as custom headers or logging context).

For teams with specific compliance requirements, the Professional tier includes an SLA and we can discuss additional security controls for enterprise deployments.

No. This site content is for product/engineering planning and should not be used as a substitute for clinical judgment.

Always route patient-care decisions through qualified clinicians and your regulated clinical governance processes.