Table 2.
Off-label indications and most common indications for antidepressant treatment, by drug
| Drug name, by class | Total No of prescriptions | Off-label indication | Treatment indications and No (%) of prescriptions | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| No | Percentage* (95% CI†) | Most common | Second most common | Third most common | ||||||||||
| Indication | No | Percentage* (95% CI†) | Indication | No | Percentage* (95% CI†) | Indication | No | Percentage* (95% CI†) | ||||||
| Selective serotonin reuptake inhibitors | ||||||||||||||
| Citalopram | 19 480 | 6988 | 35.9 (31.5 to 40.9) | Depression‡ | 12 492 | 64.1 (59.1 to 68.5) | Anxiety disorder§ | 5745 | 29.5 (25.0 to 34.6) | Panic disorder | 882 | 4.5 (2.7 to 7.2) | ||
| Paroxetine | 9212 | 94 | 1.0 (0.4 to 1.9) | Depression‡ | 4476 | 48.6 (40.2 to 57.3) | Anxiety disorder‡§ | 2719 | 29.5 (23.6 to 36.0) | Panic disorder‡ | 1563 | 17.0 (10.6 to 23.8) | ||
| Escitalopram | 7108 | 601 | 8.5 (5.7 to 11.4) | Depression‡ | 4354 | 61.3 (55.2 to 67.0) | Anxiety disorder‡§ | 2075 | 29.2 (23.2 to 35.3) | Panic disorder | 503 | 7.1 (4.6 to 9.9) | ||
| Sertraline | 6805 | 1680 | 24.7 (18.6 to 31.8) | Depression‡ | 4383 | 64.4 (55.4 to 71.8) | Anxiety disorder§ | 1847 | 27.1 (20.6 to 34.1) | Panic disorder‡ | 398 | 5.8 (2.4 to 10.0) | ||
| Fluoxetine | 2079 | 322 | 16.0 (10.0 to 24.5) | Depression‡ | 1566 | 75.3 (65.1 to 83.2) | Anxiety disorder§ | 249 | 12.0 (7.1 to 18.2) |
Panic disorder‡ | 64 | 3.1 (0.2 to 7.4) | ||
| Fluvoxamine | 924 | 265 | 28.7 (15.6 to 45.3) | Depression‡ | 592 | 64.1 (47.5 to 76.5) | Anxiety disorder§ | 233 | 25.2 (13.8 to 41.9) | OCD‡ | 71 | 7.7 (2.9 to 15.5) | ||
| Serotonin-norepinephrine reuptake inhibitors | ||||||||||||||
| Venlafaxine | 21 369 | 1501 | 7.0 (5.5 to 8.7) | Depression‡ | 14 282 | 66.8 (62.3 to 71.2) | Anxiety disorder‡§ | 5053 | 23.6 (19.4 to 27.9) | Panic disorder‡ | 782 | 3.7 (2.6 to 4.9) | ||
| Duloxetine | 2969 | 9 | 0.3 (0.0 to 1.0) | Depression‡ | 1139 | 38.4 (31.4 to 45.4) | Pain‡ | 1053 | 35.5 (27.8 to 43.1) | Fibromyalgia‡ | 604 | 20.3 (14.5 to 27.1) | ||
| Desvenlafaxine | 897 | 29 | 3.2 (0.7 to8.0) | Depression‡ | 868 | 96.8 (91.9 to 99.3) | Anxiety disorder§ | 16 | 1.8 (0.0 to 5.5) | Menopausal hot flashes | 6 | 0.7 (0.0 to 1.8) | ||
| Tricyclic antidepressants | ||||||||||||||
| Amitriptyline | 8993 | 8361 | 93.0 (89.6 to 95.7) | Pain | 4349 | 48.4 (39.7 to 57.8) | Insomnia | 2023 | 22.5 (13.6 to 31.3) | Migraine | 1501 | 16.7 (12.2 to 21.9) | ||
| Doxepin | 782 | 92 | 11.8 (3.2 to 21.3) | Insomnia‡ | 285 | 36.4 (24.1 to 49.3) | Depression‡ | 171 | 21.9 (9.7 to 35.9) | Anxiety disorder‡§ | 150 | 19.2 (9.0 to 32.0) | ||
| Nortriptyline | 592 | 458 | 77.4 (59.9 to 89.5) | Pain | 340 | 57.4 (35.0 to 74.1) | Depression‡ | 126 | 21.3 (9.5 to 38.5) | Anxiety disorder§ | 49 | 8.3 (2.4 to 20.0) | ||
| Trimipramine | 562 | 165 | 29.4 (15.9 to 43.9) | Depression‡ | 397 | 70.6 (55.9 to 84.0) | Pain | 93 | 16.5 (5.2 to 29.9) |
Insomnia | 22 | 3.9 (0.2 to 11.3) | ||
| Imipramine | 285 | 218 | 76.5 (55.4 to 90.6) | Panic disorder | 69 | 24.2 (1.6 to 42.5) | Depression‡ | 67 | 23.5 (9.4 to 44.5) | Urinary disorders | 64 | 22.5 (4.7 to 54.6) | ||
| Desipramine | 216 | 127 | 58.8 (30.5 to 80.7) | Depression‡ | 89 | 41.2 (19.2 to 69.1) | Pain | 81 | 37.5 (12.0 to 61.4) | Anxiety disorder§ | 16 | 7.4 (1.1 to 21.3) | ||
| Clomipramine | 215 | 59 | 27.4 (8.9 to 51.1) | Depression‡ | 107 | 49.8 (25.8 to 72.3) | OCD‡ | 49 | 22.8 (7.2 to 42.0) | Anxiety disorder§ | 36 | 16.7 (2.6 to 37.9) | ||
| Other | ||||||||||||||
| Trazodone | 10 070 | 8938 | 88.8 (81.5 to 93.7) | Insomnia | 8303 | 82.5 (74.5 to 88.1) | Depression‡ | 1132 | 11.2 (6.3 to 18.4) | Anxiety disorder§ | 574 | 5.7 (3.8 to 8.2) | ||
| Bupropion | 8384 | 780 | 9.3 (6.3 to 12.7) | Depression‡ | 7052 | 84.1 (79.9 to 87.9) | Nicotine dependence‡ | 565 | 6.7 (4.4 to 9.6) | ADHD | 372 | 4.4 (2.5 to 6.9) | ||
| Mirtazapine | 5908 | 622 | 10.5 (6.7 to 14.9) | Depression‡ | 5286 | 89.5 (85.1 to 93.7) | Anxiety disorder§ | 473 | 8.0 (4.3 to 13.2) | Insomnia | 157 | 2.7 (0.8 to 4.8) | ||
OCD=obsessive compulsive disorder; ADHD=attention deficit/hyperactivity disorder.
*Calculated using total number of prescriptions for the drug as the denominator.
†Calculated by a cluster bootstrap approach26 to account for non-independence of prescriptions from the same physician and for the same patient. Reported 95% confidence intervals correspond to values at the 2.5th and 97.5th percentiles of the distribution of respective estimates across 1000 bootstrap re-samples.26
‡Indications approved for drug by Health Canada or the US Food and Drug Administration as of September 2015 (end of study period).
§Includes anxiety, generalised anxiety disorder, and other anxiety disorders. Excludes panic disorder, phobias, OCD, and post-traumatic stress disorder.