• Iftikhar Adil Department of Pharmacology, Gajju Khan Medical College, Swabi, Pakistan
  • Muhammad Sajid Department of Pharmacology, Gajju Khan Medical College, Swabi, Pakistan
  • Sher Afghan Khan Department of Pharmacology, Gajju Khan Medical College, Swabi, Pakistan
  • Amjad Ali Dean, Mardan Medical complex, Mardan, Pakistan
  • Qadeer Nawaz Gajju Khan Medical College, Swabi
  • Muhammad Naeem Shahid Gajju Khan Medical College, Swabi
  • Imtiaz Khan Gajju Khan Medical College, Swabi
  • Saad . Gajju Khan Medical College, Swabi


Moxifloxacin, QT interval, Torsade de Pointes, Bazett's formula, ECG


Background: Quinolones are notorious for QT interval prolongation and sometimes carry risks for development of Torsade de Pointes. Objective of this study was to determine the effect of moxifloxacin on QT interval prolongation on electrocardiogram. Methods: It was a cross-sectional study, conducted in Medical Department of Mardan, Medical Complex, Mardan, from January to December 2021. Moxifloxacin was given for treatment of different ailments to 57 patients after approval of study protocols from Ethical Committee of Gajju Khan Medical College/Bacha Khan Medical Complex Swabi. Their baseline ECGs, second ECG on its Tmax and third set of ECGs were recorded, in triplicates, on 48 hours of treatment. QTc was calculated using Bazett’s formula either using lead II or alternatively AVR, AVF, V5, V6, or V4, leads. Moxifloxacin was administered in recommended doses. Results: Of the 57 patients, 24 patients (42%) showed QTC prolongation (prolonged QTc: For male >450 ms, and for female >470 ms); and 19 patients (33%) reached to the limits for a risk (Patients with QTc >500 ms or QTc change over baseline >60 ms) for development of Torsade de pointes. Remaining 14 patients (25%) faced no complications. Statistically significant changes were observed for both male and female patients (p<0.05). However, QT prolongation was sustained for 48 hours in female only. Conclusion: Moxifloxacin produced significant changes in QTc particularly in elderly patients. Mean changes in QTc on 48 hours were prolonged in females than males.

Pak J Physiol 2023;19(4):11–4


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Author Biographies

Iftikhar Adil, Department of Pharmacology, Gajju Khan Medical College, Swabi, Pakistan

Associate Professor of Pharmacology

Muhammad Sajid, Department of Pharmacology, Gajju Khan Medical College, Swabi, Pakistan

HOD & Professor of Pharmacology

Sher Afghan Khan, Department of Pharmacology, Gajju Khan Medical College, Swabi, Pakistan

Assistant Professor

Amjad Ali, Dean, Mardan Medical complex, Mardan, Pakistan

Dean Mardan Medical complex, Mardan.

Qadeer Nawaz, Gajju Khan Medical College, Swabi


Muhammad Naeem Shahid, Gajju Khan Medical College, Swabi


Saad ., Gajju Khan Medical College, Swabi



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How to Cite

Adil I, Sajid M, Khan SA, Ali A, Nawaz Q, Shahid MN, et al. MOXIFLOXACIN INDUCED QT INTERVAL PROLONGATION: A RISK TO TORSADE DE POINTES IN ELDERLY PATIENTS. Pak J Phsyiol [Internet]. 2023 Dec. 31 [cited 2024 Jun. 13];19(4):11-4. Available from: