R
- RA
- Rabies
- Radiation enteritis
- Radiation sickness
- Ramsay Hunt syndrome
- Rapid eye movement sleep behavior disorder
- Rapid gastric emptying
- Rapid heartbeat
- Rash, poison ivy
- Raynaud’s disease
- Reactive arthritis
- Reactive attachment disorder
- Reading disability, specific
- Rebound headache
- Rectal cancer
- Rectal inflammation
- Rectal itching
- Rectal prolapse
- Rectal ulcer
- Rectocele
- Rectovaginal fistula
- Recurrent breast cancer
- Recurrent oral ulcers
- Recurrent prostate cancer
- Red eye
- Reflux, bile
- Reflux, vesicoureteral
- Regurgitation, aortic valve
- Regurgitation, mitral valve
- Reiter’s syndrome
- REM sleep behavior disorder
- Renal artery disease
- Renal artery stenosis
- Renal cancer
- Renal lithiasis
- Renal vascular disease
- Residual limb pain
- Respiratory syncytial virus (RSV)
- Restless legs syndrome
- Retinal detachment
- Retinal diseases
- Retinoblastoma
- Retinopathy, diabetic
- Retractile testicle
- Retrograde ejaculation
- Rett syndrome
- Reye’s syndrome
- Rhabdomyosarcoma
- Rheumatic fever
- Rheumatoid arthritis
- Rhinitis, allergic
- Rhinitis, nonallergic
- Rhinitis, vasomotor
- Rib fracture
- Rickets
- Rift Valley fever
- Ringing in the ear
- Ringworm (body)
- Ringworm (scalp)
- Ringworm of the foot
- RLS
- Road rage
- Rosacea
- Roseola
- Rotator cuff injury
- Rotavirus
- Round back
- RSV
- Rubella
- Rubeola
- Rumination syndrome
- Runner’s knee
- Ruptured disk
- Ruptured eardrum (perforated eardrum)
- Ruptured spleen