Unani Concepts of Urine Formation and Micturition in Relation to Modern Renal Physiology: A Narrative Review

Background: Urine formation and micturition are essential physiological processes that maintain fluid, electrolyte, and acid-base balance. While contemporary medicine explains these processes through renal and lower urinary tract physiology and neural regulation, Unani medicine interprets them through the concepts of Akhlāṭ (humours), Quwā (faculties), and Ṭabī‘at (the governing principle of the body). Objective: To review the classical Unani concepts of urine formation and micturition and compare them with modern renal physiology through a functional correlation. Methods: A narrative review was conducted using classical Unani literature, including the works of Al-Razi, Raban Tabari, Ibn Sīnā Al-Jurjānī, along with modern textbooks and peer-reviewed articles on renal physiology. Relevant information was critically analyzed and interpreted to identify functional similarities and conceptual differences between the two systems. Results: Classical Unani literature describes urine as a waste product of hepatic digestion that undergoes further processing in the kidneys through the coordinated action of Quwwat Jādhiba, Quwwat Māsika, Quwwat Hāḍima, Quwwat Mumayyiza, and Quwwat Dāfi‘a. Micturition is explained as a coordinated process involving the kidneys, urinary bladder, urethral sphincter, abdominal muscles, and natural faculties. Functional comparison with modern physiology revealed meaningful parallels between selective separation of useful substances, urinary storage, and controlled voiding. However, differences remain in the theoretical basis of urine formation and the mechanisms regulating renal function. Conclusion: Despite their distinct conceptual frameworks, Unani medicine and contemporary renal physiology share several functional similarities in explaining urine formation and micturition. A functional interpretation of classical concepts provides a scientific basis for understanding Unani physiology while preserving its original principles. This integrative approach may support future interdisciplinary research and strengthen the scientific interpretation of Unani medicine.