Table 2.
Prevalence of the QT interval prolonging drugs with their therapeutic classes and TdP risks
| Prevalence/ classification scheme | Frequency | ||
|---|---|---|---|
| Patients: n (%)a | |||
| Overall prevalence of the QT prolonging drugs | 514 (92.6) | ||
| Gender-wise prevalence of QT prolonging drugs | |||
| Male | 256 (46.1) | ||
| Female | 258 (46.5) | ||
| Therapeutic class | TdP riskb | QT drug (ATC code) | Patients: n (%)a |
| Antimicrobials (n = 126) | Known risk of TdP (n = 98) | Ciprofloxacin (J01MA02) | 90 (16.2) |
| Clarithromycin (J01FA09) | 6 (1) | ||
| Levofloxacin (J01MA12) | 1 (0.2) | ||
| Moxifloxacin (J01MA14) | 1 (0.2) | ||
| Possible risk of TdP (n = 1) | Norfloxacin (J01MA06) | 1 (0.2) | |
| Conditional risk of TdP (n = 27) | Metronidazole (P01AB01) | 27 (4.9) | |
| Anticancer (n = 51) | Possible risk of TdP (n = 51) | Capecitabine (L01 BC06) | 46 (8.3) |
| Tamoxifen (L02BA01) | 5 (0.9) | ||
| Antidepressant (n = 4) | Conditional risk of TdP (n = 4) | Amitriptyline (N06AA09) | 3 (0.5) |
| Fluoxetine (N06AB03) | 1 (0.2) | ||
| Antidiarrheal (n = 1) | Conditional risk of TdP (n = 1) | Loperamide (A07DA03) | 1 (0.2) |
| Antiemetic (n = 571) | Known risk of TdP (n = 278) | Ondansetron (A04AA01) | 278 (50) |
| Possible risk of TdP (n = 141) | Tropisetron (A04AA03) | 139 (25) | |
| Promethazine (R06AD02) | 2 (0.4) | ||
| Conditional risk of TdP (n = 152) | Metoclopramide (A03FA01) | 152 (27.4) | |
| Antifungal (n = 11) | Known risk of TdP (n = 6) | Fluconazole (J02 AC01) | 6 (1) |
| Conditional risk of TdP (n = 5) | Amphotericin B (J02AA01) | 3 (0.5) | |
| Ketoconazole (J02AB02) | 2 (0.4) | ||
| Antihistamine (n = 8) | Conditional risk of TdP (n = 8) | Diphenhydramine (R06AA52) | 8 (1.1) |
| Antinausea (n = 21) | Known risk of TdP (n = 21) | Domperidone (A03FA03) | 21 (3.8) |
| Antineoplastic (n = 30) | Known risk of TdP (n = 30) | Oxaliplatin (L01XA03) | 30 (5.4) |
| Antipsychotic (n = 1) | Known risk of TdP (n = 1) | Haloperidol (N05 AD01) | 1 (0.2) |
| Diuretic (n = 22) | Conditional risk of TdP (n = 22) | Furosemide (C03CA01) | 19 (3.4) |
| Hydrochlorothiazide (C03AX01) | 3 (0.5) | ||
| Gonadotropin receptor agonist/antagonist (n = 1) | Possible risk of TdP (n = 1) | Leuprolide (L02AE02) | 1 (0.2) |
| Kinase inhibitor (n = 1) | Possible risk of TdP (n = 1) | Nilotinib (L01XE08) | 1 (0.2) |
| Proton pump inhibitor (n = 145) | Conditional risk of TdP (n = 145) | Esomeprazole (A02BC05) | 59 (10.6) |
| Omeprazole (A02BC01) | 86 (15.5) | ||
AZCERT Arizona Center for Education and Research on Therapeutics, TdP torsades de pointes
aPercentage calculated in total number of patients i.e., 555
bTdP risk was based on the AZCERT QT drugs lists