- Ring(s)
- Ringed hair (congenital) 757.4
- Ringing in the ear (see also Tinnitus) 388.30
- Ringworm 110.9
- Rise, venous pressure 459.89
- Risk
- Ritter's disease (dermatitis exfoliativa neonatorum) 695.81
- Rivalry, sibling 313.3
- Rivalta's disease (cervicofacial actinomycosis) 039.3
- River blindness 125.3 [360.13]
- Robert's pelvis 755.69
- Robin's syndrome 756.0
- Robinson's (hidrotic) ectodermal dysplasia 757.31
- Robles' disease (onchocerciasis) 125.3 [360.13]
- Rochalimea- see Rickettsial disease
- Rocky Mountain fever (spotted) 082.0
- Rodent ulcer (M8090/3) - see also Neoplasm, skin, malignant
- Roentgen ray, adverse effect - see Effect, adverse, x-ray
- Roetheln 056.9
- Roger's disease (congenital interventricular septal defect) 745.4
- Rokitansky's
- Rokitansky-Aschoff sinuses (mucosal outpouching of gallbladder) (see also Disease, gallbladder) 575.8
