Diarrhea continues to be a major global health concern, accounting for over 1.9 million fatalities each year, especially in children under five. Oral rehydration and antibiotics are part of the conventional treatment; nevertheless, phytotherapy, the use of plant-based treatments, and nutritional approaches provide an alternative or complementary solution, particularly in cases of antibiotic resistance or persistent diarrhea. This review explores the historical and scientific basis of phytotherapy and nutrition, as well as its pharmacological significance, clinical effectiveness, and potential integration with contemporary medicine. The growing interest in complementary therapies highlights the need for further study, despite some herbal remedies lacking solid clinical evidence. Through anti-inflammatory, anti-infectious, and gut-modulating processes, phytotherapy shows promise in reducing symptoms and improving gut health.