{"slug":"api-magentlab-com-api-calc-feurea-301e8a","title":"Fractional excretion of urea (FEUN) from BUN, urine urea nitrogen, and plasma/ur","host":"api.magentlab.com","method":"POST","resource":"https://api.magentlab.com/api/calc/feurea","category":"other","description":"Fractional excretion of urea (FEUN) from BUN, urine urea nitrogen, and plasma/urine creatinine (Carvounis 2002). Use when diuretics make FENa unhelpful. Deterministic published formula with citation; not a diagnosis.","price_listed":0.005,"price_asked":0.007,"state":"overcharges","state_label":"Asked 1.4x its listed price for its own example","checks_7d":1,"answered_7d":1,"latency_ms_median":266,"reported_calls_30d":0,"reported_payers_30d":0,"networks":["eip155:8453"],"badge":"unverified","paid_checks_7d":0,"paid_ok_7d":0,"example_input":{"body":{"items":[{"bun_mg_dl":20,"creatinine_mg_dl":2,"creatinine_umol_l":176.84,"urine_creatinine_mg_dl":100,"urine_creatinine_umol_l":8842,"urine_urea_mg_dl":200},{"bun_mg_dl":20,"creatinine_mg_dl":2,"creatinine_umol_l":176.84,"urine_creatinine_mg_dl":100,"urine_creatinine_umol_l":8842,"urine_urea_mg_dl":200}]},"method":"POST","type":"http"},"output_schema":{"$schema":"https://json-schema.org/draft/2020-12/schema","properties":{"input":{"additionalProperties":false,"properties":{"body":{"additionalProperties":false,"properties":{"items":{"items":{"properties":{"bun_mg_dl":{"description":"Blood urea nitrogen in mg/dL (1-200). Same units as urine urea nitrogen.","type":"number"},"creatinine_mg_dl":{"description":"Plasma creatinine in mg/dL. Provide this or creatinine_umol_l.","type":"number"},"creatinine_umol_l":{"description":"Plasma creatinine in µmol/L. Converted as mg/dL = µmol/L / 88.42.","type":"number"},"urine_creatinine_mg_dl":{"description":"Urine creatinine in mg/dL (1-500). Provide this or urine_creatinine_umol_l.","type":"number"},"urine_creatinine_umol_l":{"description":"Urine creatinine in µmol/L (88-44210). Converted as mg/dL = µmol/L / 88.42.","type":"number"},"urine_urea_mg_dl":{"description":"Urine urea nitrogen in mg/dL (1-2000). Same units as BUN.","type":"number"}},"required":["bun_mg_dl","urine_urea_mg_dl"],"type":"object"},"maxItems":25,"minItems":1,"type":"array"}},"required":["items"],"type":"object"},"headers":{"additionalProperties":{"type":"string"},"type":"object"},"method":{"const":"POST","type":"string"},"type":{"const":"http","type":"string"}},"required":["type","method"],"type":"object"},"output":{"properties":{"example":{"type":"object"},"type":{"type":"string"}},"required":["type"],"type":"object"}},"required":["input"],"type":"object"},"history":[{"day":"2026-09-28","reachable":true,"status":402,"valid_402":true,"asked_usdc":0.007,"price_match":false,"latency_ms":266,"error":null}],"description_full":"Fractional excretion of urea (FEUN) from BUN, urine urea nitrogen, and plasma/urine creatinine (Carvounis 2002). Use when diuretics make FENa unhelpful. Deterministic published formula with citation; not a diagnosis.","last_updated":"2026-09-28T13:53:36.322Z","schemes":["exact"]}