- Iliotibial band friction syndrome 728.89
- Ill, louping 063.1
- Illegitimacy V61.6
- Illness - see also Disease
- Imbalance 781.2
- Imbecile, imbecility 318.0
- Imbedding, intrauterine device 996.32
- Imbibition, cholesterol (gallbladder) 575.6
- Imerslund (-Gräsbeck) syndrome (anemia due to familial selective vitamin B12 malabsorption) 281.1
- Iminoacidopathy 270.8
- Iminoglycinuria, familial 270.8
- Immature - see also Immaturity
- Immaturity 765.1
- Immersion 994.1
- Immobile, immobility
- Immunization
- Immunodeficiency 279.3
- Immunotherapy, prophylactic V07.2
- Impaction, impacted
- Impaired, impairment (function)
- Impaludism - see Malaria
- Impediment, speech NEC 784.5
