Frequency of adverse drug events and medication errors according to each drug class
| Drug class | ADEs, n (%) (n=1207) | All MEs, n (%) (n=600) | Preventable ADEs, n (%) (n=437) | Potential ADEs, n (%) (n=147) | MEs without risk of injury, n (%) (n=16) |
| Psychotropic drugs | 688 (57.0) | 320 (53.3) | 293 (67.1) | 26 (17.7) | 1 (6.2) |
| Sedatives (BZDRA) | 189 (15.7) | 141 (23.5) | 137 (31.4) | 4 (2.7) | 0 (0) |
| Antipsychotics (atypical) | 189 (15.7) | 55 (9.2) | 47 (10.8) | 8 (5.4) | 0 (0.0) |
| Mood stabilisers | 101 (8.4) | 40 (6.7) | 37 (8.5) | 3 (2.0) | 0 (0.0) |
| Antipsychotics (typical) | 53 (4.4) | 9 (1.5) | 8 (1.8) | 1 (0.7) | 0 (0.0) |
| Antidementia medicines | 50 (4.1) | 20 (3.3) | 20 (4.6) | 0 (0.0) | 0 (0.0) |
| Anti-parkinsonian drugs | 41 (3.4) | 35 (5.8) | 25 (5.7) | 9 (6.1) | 1 (6.3) |
| Anxiolytics | 34 (2.8) | 11 (1.8) | 11 (2.5) | 0 (0.0) | 0 (0.0) |
| Antidepressants (SSRI, SNRI,NaSSA) | 16 (1.3) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| Antidepressants (other) | 13 (1.1) | 8 (1.3) | 8 (1.8) | 0 (0.0) | 0 (0.0) |
| Sedatives (other) | 1 (0.1) | 1 (0.2) | 0 (0.0) | 1 (0.7) | 0 (0.0) |
| Anticonvulsants (except for mood stabilisers) | 1 (0.1) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| Non-psychotropic drugs | 519 (43.0) | 280 (46.7) | 144 (33.0) | 121 (82.3) | 15 (93.8) |
| Antihypertensives | 120 (9.9) | 46 (7.7) | 35 (8.0) | 11 (7.5) | 0 (0.0) |
| Laxatives | 115 (9.5) | 35 (5.8) | 11 (2.5) | 22 (15.0) | 2 (12.5) |
| Fluids and electrolytes | 84 (7.0) | 122 (20.3) | 80 (18.3) | 42 (28.6) | 0 (0.0) |
| Anticoagulants | 61 (5.1) | 6 (1.0) | 1 (0.2) | 5 (3.4) | 0 (0.0) |
| Anti-inflammatory drugs | 24 (2.0) | 3 (0.5) | 0 (0.0) | 2 (1.4) | 1 (6.3) |
| Antiallergic agents | 18 (1.5) | 5 (0.8) | 4 (0.9) | 1 (0.7) | 0 (0.0) |
| Cardiovascular drugs | 19 (1.6) | 12 (2.0) | 3 (0.7) | 9 (6.1) | 0 (0.0) |
| Antibiotics | 13 (1.1) | 10 (1.7) | 3 (0.7) | 6 (4.1) | 1 (6.3) |
| Chinese herbal medicines | 8 (0.7) | 7 (1.2) | 1 (0.2) | 1 (0.7) | 0 (0.0) |
| Peptic ulcer drugs | 7 (0.6) | 2 (0.3) | 0 (0.0) | 1 (0.7) | 1 (6.3) |
| Antidiabetics | 6 (0.5) | 9 (1.5) | 0 (0.0) | 9 (6.1) | 0 (0.0) |
| Lipid-lowering agents | 3 (0.3) | 2 (0.3) | 1 (0.2) | 1 (0.7) | 0 (0.0) |
| Other drugs | 41 (3.4) | 21 (3.5) | 5 (1.1) | 11 (7.5) | 5 (31.3) |
| All drugs | 1207 (100) | 600 (100) | 437 (100) | 147 (100) | 16 (100) |
ADEs, adverse drug events; BZDRA, benzodiazepine receptor agonists; MEs, medication errors; NaSSA, noradrenergic and specific serotonin antidepressants; SNRI, serotonin–norepinephrine reuptake inhibitor; SSRI, selective serotonin reuptake inhibitor.