- Reduced ventilatory or vital capacity 794.2
- Reduction
- Redundant, redundancy
- Reduplication - see Duplication
- Referral
- Reflex - see also condition
- Reflux 530.81
- Reformed gallbladder 576.0
- Reforming, artificial openings (see also Attention to, artificial, opening) V55.9
- Refractive error (see also Error, refractive) 367.9
- Refsum's disease or syndrome (heredopathia atactica polyneuritiformis) 356.3
- Refusal of
- Regaud
- Regional - see condition
- Regulation feeding (elderly) (infant) 783.3
- Regurgitated
- Regurgitation 787.03
- Rehabilitation V57.9
- Reichmann's disease or syndrome (gastrosuccorrhea) 536.8
- Reifenstein's syndrome (hereditary familial hypogonadism, male) 259.52
- Reilly's syndrome or phenomenon (see also Neuropathy, peripheral, autonomic) 337.9
- Reimann's periodic disease 277.31
