- Patulous - see also Patent
- Pause, sinoatrial 427.81
- Pavor nocturnus 307.46
- Pavy's disease 593.6
- Paxton's disease (white piedra) 111.2
- Payr's disease or syndrome (splenic flexure syndrome) 569.89
- PBA (pseudobulbar affect) 310.8
- Pearl-workers' disease (chronic osteomyelitis) (see also Osteomyelitis) 730.1
- Pearls
- Pectenitis 569.49
- Pectenosis 569.49
- Pectoral - see condition
- Pectus
- Pedatrophia 261
- Pederosis 302.2
- Pediculosis (infestation) 132.9
- Pediculus (infestation) - see Pediculosis
- Pedophilia 302.2
- Peg-shaped teeth 520.2
- Pel's crisis 094.0
- Pel-Ebstein disease - see Disease, Hodgkin's
- Pelade 704.01