_____________________________________________________________________________________________________ ≡ Resident; ⱷ Professor; # Assistant Professor; † Senior Registrar; *Corresponding author: E-mail: nadeem.chohan@lumhs.edu.pk, nadeemchohanpink76@yahoo.com; Journal of Pharmaceutical Research International 33(53B): 252-257, 2021; Article no.JPRI.77518 ISSN: 2456-9119 (Past name: British Journal of Pharmaceutical Research, Past ISSN: 2231-2919, NLM ID: 101631759) Frequency of Thrombocytopenia in Neonates Following Phototherapy in Neonatology Unit of Tertiary Care Hospital Hina Naqvi a≡ , Shazia Memon aⱷ , Mushtaque Ali Shah a† , Muhammad Nadeem Chohan a*# , Numra Shaikh a≡ and Fiza Shah a≡ a Pediatrics Department LUMHS, Jamshoro, Pakistan. Authors’ contributions This work was carried out in collaboration among all authors. All authors read and approved the final manuscript. Article Information DOI: 10.9734/JPRI/2021/v33i53B33703 Editor(s): (1) Takashi Ikeno, National Institute of Mental Health, National Center of Neurology and Psychiatry, Japan. Reviewers: (1) Dharma Lindarto, Universitas Sumatera Utara, Indonesia. (2) Akila Prashant, JSS Medical College, India. Complete Peer review History, details of the editor(s), Reviewers and additional Reviewers are available here: https://www.sdiarticle5.com/review-history/77518 Received 30 September 2021 Accepted 28 November 2021 Published 08 December 2021 ABSTRACT Aim: To determine the frequency of thrombocytopenia and its severity in relation to level of indirect hyperbilirubinemia in neonates following phototherapy at tertiary care hospital. Study Design: Descriptive study Place and duration: This study was conducted at Paediatric department (neonatal ward), Liaquat University Hospital, Hyderabad, from 1 st August 2020 till 31 st Jan 2021 Methodology: All neonates who fulfilled the inclusion criteria presented at pediatric department (neonatal ward), Liaquat University Hospital Hyderabad were included in the study. After written consent, brief history was taken from the mother or family member and complete blood count (CBC) was sent to check the baseline platelet count along with total serum bilirubin, it was repeated after 48 hours of phototherapy. Results: Out of 231 neonates 70 (30.3%) developed thrombocytopenia after phototherapy. In our study 117 neonates (50.6%) were males & 114 neonates (49.4%) were females with the mean age Original Research Article