Articles: J
- Jackson
- Jacques Joseph Grancher
- Jadassohn
- Jakob
- Jalapa
- James Wylie
- James Young Simpson
- Janet Method
- Janselm
- Janus Green B
- Janus Parasiticus
- Japan
- Jarisch-Herxheimer Reaction
- Jaundice
- Javelle Water
- Jaws
- Jean Louis Petit
- Jean Paul Marat
- Jejunostomy
- Jirgei Waters → see Transbaikal Resorts
- Johann Mikulicz-Radecki
- Johann Veit
- Johann Weyer
- Johannes Müller
- Johannes Orth
- John Newport Langley
- Joint
- Joint Mouse
- Joints
- Jolly Bodies
- Josef Hyrtl
- Josef Skoda
- Joseph Babinski
- Joule
- Jugular Veins
- Jules Bordet
- Jules Dejerine
- Jumps
- Juniper Berries
- Justus von Liebig
- Juvenile Delinquency