en سم شناسی Toxicology پژوهشي Original Research <span style="font-size:11pt"><span style="line-height:200%"><span calibri="" style="font-family:"><b><span style="font-size:12.0pt"><span style="line-height:200%"><span new="" roman="" style="font-family:" times="">Background:</span></span></span></b><span style="font-size:12.0pt"><span style="line-height:200%"><span new="" roman="" style="font-family:" times=""> Vitamin A (VA) has lots of physiological functions in humans. However, excessive intake causes a condition known as hypervitaminosis A (HA), leading to arrays of health issues. <b>Methods:</b> This research evaluated the effect of HA on selected blood parameters, liver, kidney and stomach. A total of 12 adult male Wister rats, weighing 180-240g were divided into two groups (1 and 2) of 6 rats. Group 1 served as control and received feed and distilled water only while group 2 (test group) received 14,286 IU/rat/day of VA orally for two weeks in addition to feed and distilled water. At the end of the experiment, blood samples were collected for biochemical and hematological analysis while the organs of interest (liver, kidney and stomach) were harvested and processed for histological evaluation. Data obtained were considered statistically significant at p&le; 0.05. <b>Results:</b> Results showed that HA caused a statistically lowered red blood cell count, hemoglobin, eosinophil, packed cell volume as well as liver enzymes (aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase). There were however significantly higher (p˂ 0.05) platelet count, urea, creatinine and potassium concentrations in VA treated rats when compared to control. Treated group had renal degeneration, dilated liver sinusoids and slightly degenerated hepatocytes. However, the microarchitecture of the stomach appeared normal in both groups. <b>Conclusion:</b> High dose VA ingested within a short period of time (14 days) caused adverse effects on the blood components as well as the histology of the kidney and liver.</span></span></span></span></span></span><br type="_moz" > <br> &nbsp; blood, hypervitaminosis A, kidney, liver, vitamin A 0 0 http://pbr.mazums.ac.ir/browse.php?a_code=A-10-1360-1&slc_lang=en&sid=1 Ezinne Uchechi Ekwujuru 221000429@edu.vut.ac.za 100319475328460012410 100319475328460012410 Yes Department of Natural Sciences, Faculty of Vaal University of Technology, South Africa Uzozie Chikere Ofoego uc.ofoego@unizik.edu.ng 100319475328460012411 100319475328460012411 No Department of Anatomy, Faculty of Basic Medical SciencesNnamdi Azikiwe University, Nnewi Campus, Nnewi, Nigeria Amarachukwu Ndubuisi Ofoego amarachukwuofoego2018@gmail.com 100319475328460012412 100319475328460012412 No Imo State University Owerri, Nigeria