I
- IBD
- IBS
- Idiopathic hypersomnia
- Idiopathic intracranial hypertension
- Idiopathic myelofibrosis
- Idiopathic thrombocytopenic purpura
- Idiopathic toe walking
- IgA nephropathy (Berger disease)
- IgA vasculitis
- IIH
- Illness anxiety disorder
- Immune thrombocytopenia (ITP)
- Immune thrombocytopenic purpura
- Impacted wisdom teeth
- Impaired glucose tolerance
- Impetigo
- Impotence
- Inborn error of metabolism
- Incompetent cervix
- Incontinence, bowel
- Incontinence, fecal
- Incontinence, urinary
- Indigestion
- Infant jaundice
- Infant reflux
- Infantile hemangioma
- Infectious arthritis
- Infectious diseases
- Infertility
- Infertility, female
- Infertility, male
- Inflamed gallbladder
- Inflamed pancreas
- Inflamed pericardium
- Inflammatory bowel disease (IBD)
- Inflammatory breast cancer
- Influenza (flu)
- Influenza, avian
- Influenza, H1N1
- Influenza, swine flu
- Ingrown hair
- Ingrown toenails
- Inguinal hernia
- Inherited metabolic disorders
- Insomnia
- Insulin resistance syndrome
- Interdigital neuroma
- Intermittent claudication
- Intermittent explosive disorder
- Interstitial cystitis
- Interstitial lung disease
- Intestinal ischemia
- Intestinal lipodystrophy
- Intestinal obstruction
- Intracranial aneurysm
- Intracranial hematoma
- Intracranial venous malformations
- Intraductal carcinoma
- Intrahepatic cholestasis of pregnancy
- Intussusception
- Invasive lobular carcinoma
- Iritis
- Iron deficiency anemia
- Iron overload
- Irritable bowel syndrome
- Ischemia, intestinal
- Ischemic bone necrosis
- Ischemic colitis
- Ischemic priapism
- Islet cell cancer
- Itchy skin (pruritus)
- ITP