- Abandonment NEC (causing exposure to weather conditions) (with intent to injure or kill), X58
- Abuse (adult) (child) (mental) (physical) (sexual), X58
- Accident (to), X58
- Acid throwing (assault), Y08.89
- Activity (involving) (of victim at time of event), Y93.9
- Adverse effect of drugs, see Table of Drugs and Chemicals
- Aerosinusitis, see Air, pressure
- After-effect, late, see Sequelae
- Air,
- Alpine sickness, W94.11
- Altitude sickness, W94.11
- Anaphylactic shock, anaphylaxis, see Table of Drugs and Chemicals
- Andes disease, W94.11
- Arachnidism, arachnoidism, X58
- Arson (with intent to injure or kill), X97
- Asphyxia, asphyxiation,
- Aspiration,
- Assassination (attempt), see Assault
- Assault (homicidal) (by) (in), Y09
- Attack by mammals NEC, W55.89
- Avalanche, see Landslide
- Aviator”s disease, see Air, pressure