• 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


Download data is not yet available.

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



Hansen RN, Suh K, Serbin M, Yonan C, Sullivan SD. Cost-effectiveness of opicapone and entacapone in reducing OFF-time in Parkinson’s disease patients treated with levodopa/carbidopa. J Med Econ 2021;(1):563–9.

Malik M, Hnatkova K, Schmidt A, Smetana P. Electrocardiographic QTc changes due to moxifloxacin infusion. J Clinical Pharmacol 2009;49(6):674–83.

Müller T, Schlegel E, Zingler S, Thiede HM. Effects of one-day application of levodopa/carbidopa/entacapone versus levodopa/ carbidopa/opicapone in Parkinson’s disease patients. Cells 2022;11(9):1511.

Kuryshev YA, Brown AM, Wang L, Benedict CR, Rampe D. Interactions of the 5-hydroxytryptamine 3 antagonist class of antiemetic drugs with human cardiac ion channels. J Pharmacol Exp Ther 2000;295(2):614–20.

Schlepper M. Hämodynamik bel supraventrikulären Tachykardien und deren Behandlung In: Lúderitz B. (Ed). Arrhythmiebehandlung und Hämodynamik. Berlin Heidelberg: Springer; 1990.p. 82–102.

Mulla W, Murninkas M, Levi O, Etzion Y. Incorrectly corrected? QT interval analysis in rats and mice. Front Physiol 2022;13:1002203.

Yap YG, Camm AJ. Drug induced QT prolongation and Torsade de Pointes. Heart 2003;89(11):1363–72.

Khan IA. Long QT syndrome: diagnosis and management. Am Heart J 2002;143(1)7–14.

Sedgwick ML, Lip G, Rae AP, Cobbe SM. Chemical cardioversion of atrial fibrillation with intravenous dofetilide. Int J Cardiol 1995;49(2):159–66.

D’Alnoncourt CN, Zierhut W, Blüderitz B. “Torsade de pointes” tachycardia. Re-entry or focal activity? Br Heart J 1982;48(3):213–6.

Lasser KE, Allen PD, Woolhandler SJ, Hirmnelstein DU, Wolfe SM, Bor DH. Timing of new black box warnings and withdrawals for prescription medications. JAMA 2002;287(17):2215–20.

Sheehan G, Chew NY. The history of quinolones, In: Ronald AR, Low DE. (Eds). Fluoroquinolone Antibiotics. Cambridge: Birkhäuser Basel Springer; 2003.p. 1–10.

Locati EH, Zareba W, Moss AJ, Schvwartz PJ, Vincent GM, Lehmann MH, et al. Age- and se1-related differences in clinical manifestations in patients with congenital long-QT syndrome: findings from the international LQTS Registry. Circulation 1998;97(22):2237–44.

Reardon M, Malik M. QT interval changes with age in an overtly healthy older population. Clin Cardiol 1996;19(12):949–52.

Priori SG, Schwartz PJ, Napolitano C, Bloise R, Ronchetti E, Grillo M, et al. Risk stratification in the long-QT syndrome. N Engl J Med 2003;348(19):1866–74.

Pratt CM, Ruberg S, Morganroth J, McNutt B, Woodward J, Harris S, et al. Dose-response relation between terfenadine (Seldane) and the OTC interval on the scalar electrocardiograrm: distinguishing a drug effect from spontaneous variability. Am Heart J 1996;131(3):472–80.

Johannesen L, Garnett C, Malik M. Impact of electrocardiographic data quality on moxifloxacin response in thorough OT/OTC Studies. Drug Saf 2014;37(3):183–9.

Moon SJ, Lee J, An H, Yim DS, Chung JY, Yu KS, et al. The effects of moxifloxacin on QTc interval in healthy Korean male subjects. Drugs R D. 2014;14(2):63–71.

Mason JW, Moon TE, O’Boyle E, Dietz A. A randomized, placebo-controlled, four-period crossover, definitive QT study of the effects of APF530 exposure, high-dose intravenous granisetron, and moxifloxacin on QTc prolongation. Cancer Manag Res 2014;6:181–90.

Cowan JC, Yusoff K, Moore M, Amos PA, Gold AE, Bourke JP, et al. Importance of lead selection in QT interval measurement. Am J Cardiol 1988;61(1):83–7.

Brouwer J, Van Den Berg MP, Grobbee DE, Haaksma J, Wilde AA. Diagnostic performance of various QTc interval formulas in a large family with long QT syndrome type 3: Bazett’s formula not so bad after all. Ann Noninvasive Electrocardiol 2003;8(4):269–74.

Crouch MA, Limon L, Cassano AT. Clinical relevance and management of drug-related QT interval prolongation. Pharmacotherapy 2003;23(7):881–908.

Owens RC Jr. Risk assessment for antimicrobial agent-induced QTc interval prolongation and Torsade de Pointes. Pharmacotherapy 2001;21(3):301–19.

Tsikouris JP, Peeters MJ, Cox CD, Meyerrose GE, Seifert CF. Effects of three fluoroquinolones on QT analysis after standard treatment courses. Ann Noninvasive Electrocardiol 2006;11(1):52–6.

Zeltser D, Justo D, Halkin A, Prokhorov V, Heller K, Viskin S. Torsade de pointes due to noncardiac drugs: most patients have easily identifiable risk factors. Medicine (Baltimore) 2003;82(4):282–90.

Shah RR. The significance of QT interval in drug development. Br J Clin Pharmacol 2002;54(2):188–202.

US FDA. Adverse Event Reporting System (FAERS) Public Dashboard. Available at: [Accessed: 5 Aug 2018]

Khan F, Ismail M, Khan Q, Ali Z. Moxifloxacin-induced QT interval prolongation and Torsade de Pointes: a narrative review. Expert Opin Drug Saf 2018;17(10):1029–39.




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 Feb. 27];19(4):11-4. Available from: