https://www.selleckchem.com/products/sodium-phenylbutyrate.html Backround and Aim Cyclophosphamide (CP) is a drug used for treatment of many malignant diseases. However, it can cause serious side effects such as hemorrhagic cystitis and male infertility. Hydrogen sulfide (H2S) is a gaseous mediator and is suggested to have antioxidant, anti-inflammatory and antiapoptotic effects. In this study, dose-dependent effects of H2S donor sodium hydrosulfide (NaHS) on cyclophosphamide-induced hemorrhagic cystitis and testicular dysfunction were investigated in rats. Method Rats were divided into 5 groups (n = 8) control, CP, NaHS25 µmol / kg, NaHS50 µmol / kg, NaHS100 µmol / kg. After treatment for 7 days intraperitoneally (ip), a single ip dose of CP 200 mg / kg was given on the 8th day. Then, treatment was continued for 7 days. In bladder and testicular tissues, IL-6, IL10, cGMP, NO, H2S, FSH, LH and Testosterone levels were measured by ELISA. Histopathological examination with H&E staining as well as immunohistochemical staining for acrolein in bladder and Caspase-3 and APAF-1 in testis were performed. Results NaHS prevented the increased IL6 and IL10 values induced by CP as well as prevented the decrease in cGMP values associated with CP. There was no significant change in FSH values, but the LH value, which increased with CP, decreased with 25,50 and 100 µmol / kg NaHS. In contrast, testosterone decreased in the CP group and increased in the treatment groups. NaHS was effective in many biochemical and histopathological parameters at 25 and 50 µmol / kg doses, and this effect decreased at 100 µmol / kg dose. Conclusion H2S has a protective and therapeutic effect on hemorrhagic cystitis and testicular dysfunction induced by cyclophosphamide, It can be suggested that H2S is a promising molecule in facilitating cancer treatment. Despite the use of ultrasound guidance, a significant part of thyroid biopsies are nondiagnostic (ND). We aimed to investigate the utility of the p