Repeated MANOVA revealed no significant differences among groups in blood urea nitrogen (BUN) (p = 0.62) and creatinine (CRE) (p = 0.27), and the ratio of BUN/CRE (BCr) (p = 0.20). An overall Wilks' Lambda analysis showed significant time effects (p < 0.01) in mean changes in BUN (unit conversion to mg/dl by mmol/l × 2.8011) (2.79mg/dl; 1.58, 4.00) at week 8, CRE (unit conversion to mg/dl by µmol/l × 0.0113) (-0.35mg/dl; -0.49, -0.21) at week 4 and (-0.16mg/dl; -0.28, -0.05), and BCr: (8.17; 4.01, 12.33) at week 4 and (7.02; 3.02, 11.02) at week 8. Greenhouse-Geisser univariate analysis revealed no time × group interaction of BUN (p = 0.54), CRE (p = 0.78), and BCr (p = 0.62). In liver enzymes, there were no significant differences among groups in alkaline phosphatase (ALP) (p = 0.24), alanine amino transferase (ALT) (p = 0.74), and aspartate amino transferase (AST) (p = 0.47). Delta analysis revealed significant difference in ALP: (-11.23 U/L; -13.93, -8.5) at week 4 and (-5.44 U/L; -8.48, -2.4) at week 8. LSD Post hoc analysis revealed no significant mean changes in liver enzymes; however, there was a significant difference (p = 0.04) of ALP between PWS+S (-3.44 U/L; -6.52, -0.36) and PWS (-7.86 U/L; -10.88, -4.84) compared with P (-5.36 U/L; -8.388, -2.34). However, the range of both groups PWS+S: (68.14 ± 17.39 U/L) at week 4 and (74.44 ± 19.64 U/L) at week 8 and PWS: (87.20 ± 24.72 U/L) at week 4 and (78.49 ± 24.96 U/L) at week 8 were within safe clinical range (30-92 U/L). There were no significant time (p = 0.23) and time × group interaction (p = 0.78) of creatine kinase (CK) and lactate dehydrogenase (LDH), no significant time × group interaction (p = 0.78) of total cholesterol, LDL-C, HDL-C and triglyceride, and a significant time effect (p < 0.01) but no time × group effect (p = 0.083) of glucose levels.