Diagnosaurus
- Facial erythema
- Facial pain
- Facial palsy
- Factitious disorder
- Failure to thrive
- Falls & gait disorders
- Fascioliasis (sheep liver fluke)
- Fatigue
- Fatigue and fever
- Fatigue and weight gain
- Fatigue and weight loss
- Fat necrosis of the breast
- Fatty liver disease
- Fatty liver of pregnancy
- Fecal incontinence
- Fecal occult blood test, positive
- Female hypogonadism
- Ferritin, decreased
- Ferritin, increased
- Fever
- Fever, hospital-acquired
- Fever, postoperative
- Fever, postpartum
- Fever, relapsing or recurrent
- Fever and abdominal pain
- Fever and neck pain
- Fever and peripheral neuropathy
- Fever and rash
- Fever and weight loss
- Fever in immunocompromised
- Fever in parenteral drug user
- Fever in returning traveler
- Fever of unknown origin
- Fibrillation, atrial
- Fibrillation, ventricular
- Fibroadenoma, breast
- Fibrocystic breast disease
- Fibroids, uterine
- Fibromuscular dysplasia
- Fibromyalgia
- Figurate (shaped) erythemas
- Filariasis
- Fistula, perianal
- Fixed drug eruption
- Flatfoot
- Flatus (flatulence)
- Flexor (volar) tenosynovitis
- Floaters
- Flutter, atrial
- Focal segmental glomerulosclerosis
- Folic acid deficiency
- Folliculitis
- Foot drop
- Foot pain
- Foreign-body aspiration
- Fracture, pathologic
- Frequency, urinary
- Fulminant hepatic failure
- FUO
- FUO in HIV/AIDS
- Furuncles