Characteristics of worst overdose experience symptoms by overdose substance group (n=314), 2021–2022, USA
| Symptoms | Alcohol only n=115 (36.6%) n (%) | Alcohol and cannabis n=88 (28.0%) n (%) | Alcohol and other substances n=71 (22.6%) n (%) | Other substances (no alcohol) n=40 (12.7%) n (%) |
| High risk: alteration in mental status | ||||
| Awake, but no memory of what happened*** | 65 (56.5%) | 57 (64.7%) | 52 (73.2%) | 13 (32.5%) |
| Lost consciousness* | 32 (27.8%) | 25 (28.4%) | 35 (49.2%) | 14 (35.0%) |
| Could not be woken up | 12 (10.4%) | 8 (9.0%) | 16 (22.5%) | 7 (17.5%) |
| High risk: physical symptoms | ||||
| Collapsed* | 10 (8.6%) | 8 (9.0%) | 16 (22.5%) | 9 (22.5%) |
| Skin turned blue or pale* | 5 (4.3%) | 8 (9.0%) | 9 (12.6%) | 8 (20.0%) |
| Difficulty breathing*** | 7 (6.0%) | 10 (11.3%) | 17 (23.9%) | 12 (30.0%) |
| Had convulsions* | 0 (0.0%) | 4 (4.5%) | 5 (7.0%) | 3 (7.5%) |
| Had a heart attack | 0 (0.0%) | 0 (0.0%) | 2 (2.8%) | 2 (1.5%) |
| Low risk: alteration in mental status | ||||
| Had hallucinations*** | 5 (4.3%) | 15 (17.0%) | 26 (36.6%) | 10 (25.0%) |
| Low risk: physical symptoms | ||||
| Vomiting/nausea* | 111 (96.5%) | 86 (97.7%) | 69 (97.1%) | 35 (87.5%) |
| Heart beating fast/slow*** | 18 (15.6%) | 35 (39.7%) | 43 (60.6%) | 20 (50.0%) |
| Was shaking*** | 21 (18.2%) | 18 (20.5%) | 38 (53.5%) | 22 (55.0%) |
| Had a fever/felt too cold*** | 11 (9.5%) | 12 (13.6%) | 23 (32.3%) | 10 (25.0%) |
*p<0.05.
**p<0.01.
***p<0.001.