/v1/interchangeability/checkTwo product codes return whether FDA rates the products interchangeable, with the outcome, the reason and each product’s own rating. subject is the product of code; swapping the codes swaps subject and comparator and keeps the verdict, including the reason.
AuthorizationstringRequiredBearer token with your API key. Keep the key server-side.
Idempotency-KeystringOptionalMakes a retry count once. 8 to 128 letters, digits and . _ : / + -, starting with a letter or digit. For 24 hours the key is bound to your workspace and the exact request; reusing it for different work is refused with 409.
Send the fields as a JSON body.
codestringRequiredat most 512 charactersAny code CODE-LOOKUP reads as one product. A code naming several products or a Drug is 409 with candidates.
compare_withstringRequiredat most 512 charactersThe other product’s code, read the same way.
One object. Optional fields are left out when empty; a few return null for unknown, as their sentences say. Dates are YYYY-MM-DD and times ISO 8601 UTC.
interchangeablebooleanOptionalTrue where an FDA rating establishes it, false where FDA’s rating says no, absent where FDA rates no such pair.
outcomestringRequiredWhy: equivalent or interchangeable_biologic when FDA rates the pair; same_product for one product sent twice; otherwise the reason FDA rates no such pair.
reasonstringOptionalThe detail behind outcome, such as no_application or different_strength. When both products are unrated for different reasons, the one that sorts first.
subjectRatedProductRequiredThe first product, with its FDA rating.
comparatorRatedProductRequiredThe second product, with its FDA rating.
Errors and limits lists every code and the limits behind them.