5-Minute Emergency Consult
- Obstructive shock
- Obtundation
- Ocular injuries, in blow-out fracture
- Ocular toxoplasmosis
- Odynophagia
- Oophoritis
- Opiate toxidrome
- Opisthotonos
- Oral poliovirus vaccine (OPV)
- Orbital floor fractures, blow-out
- Orchitis
- Organ transplantation, immunosuppression from
- Oropharyngeal (transfer) dysphagia
- Osmol gap
- Ossification, in ankylosing spondylitis
- Overuse syndrome