- GAD
- Gallbladder removal
- Gallstones
- Ganglion, excision of
- Gangrene
- Gastrectomy
- Gastroenteritis
- Gastroenteritis in children
- Gastroesophageal reflux disease
- Gastroscopy
- Gender dysphoria
- Genetics
- Genital herpes
- Genital warts
- Giardiasis
- Gilbert's syndrome
- Gingivitis and periodontitis
- Glandular fever
- Glaucoma
- Glomerulonephritis
- Glue ear
- Goitre
- Gonorrhoea
- Gout
- Gram stain
- Grazes
- Guillain-Barré syndrome
- Gum disease