“Explore our comprehensive A-Z guide on diseases and conditions. Discover detailed information on definitions, symptoms, causes, and treatments to better understand various health issues.”
- Obesity
- Obesity Hypoventilation Syndrome
- Obesophobia
- Oblique Fracture
- Obsessive-Compulsive Disorder (OCD)
- Obsessive-Compulsive Personality Disorder (OCPD)
- Obstructed Defecation
- Obstructive Shock
- Obstructive Sleep Apnea
- Obstructive Sleep Apnea in Children
- Occipital Neuralgia
- Occupational and Work-Related Asthma
- Octophobia
- Ocular Herpes
- Ocular Hypertension
- Ocular Ischemic Syndrome
- Ocular Migraine
- Ocular Rosacea
- Ocular Syphilis
- Oculopharyngeal Muscular Dystrophy
- Ogilvie Syndrome
- Oligoarthritis
- Oligodendroglioma
- Oligohydramnios
- Oligomenorrhea
- Oligospermia
- Oliguria
- Ombrophobia
- Omentum Cancer
- Omphalitis
- Omphalocele
- Onchocerciasis
- Onycholysis
- Open Globe Injury
- Ophidiophobia
- Opiate and Opioid Withdrawal
- Opioid Overdose
- Opioid Use Disorder
- Oppositional Defiant Disorder (ODD)
- Optic Atrophy
- Optic Disc Drusen
- Optic Nerve Hypoplasia
- Optic Neuritis
- Oral Allergy Syndrome
- Oral Cancer
- Oral Health Problems and Diabetes
- Oral Herpes
- Oral Lichen Planus
- Oral Mucocele
- Orbital Cellulitis
- Orbital Fractures
- Orchitis
- Organ Failure
- Organophosphate Poisoning
- Ornithophobia
- Orofacial Granulomatosis
- Oropharyngeal Cancer
- Oropharyngeal Human Papillomavirus (HPV) Infection
- Oropouche Virus Disease
- Orthopoxvirus
- Orthostatic Hypotension
- Orthostatic Proteinuria
- Orthostatic Tremor
- Os Trigonum Syndrome
- Osgood-Schlatter Disease
- Ossifying Fibroma
- Osteitis Fibrosa Cystica (OFC)
- Osteitis Pubis
- Osteoarthritis
- Osteoarthritis of the Knee
- Osteoblastoma
- Osteochondritis Dissecans
- Osteochondroma
- Osteogenesis Imperfecta
- Osteoid Osteoma
- Osteomalacia
- Osteomyelitis
- Osteonecrosis of the Jaw (ONJ)
- Osteopenia
- Osteopoikilosis
- Osteoporosis
- Osteoradionecrosis (ORN)
- Osteosarcoma
- Otorrhea
- Otosclerosis
- Ototoxicity
- Ovarian Cancer
- Ovarian Cysts
- Ovarian Dermoid Cyst
- Ovarian Endometrioma
- Ovarian Germ Cell Tumors
- Ovarian Hyperstimulation Syndrome (OHSS)
- Ovarian Torsion
- Overactive Bladder
- Overbite
- Overeating
- Overflow Incontinence
- Overjet
- Overpronation
- Overriding Aorta
- Overtraining Syndrome
- Overweight
- Ovulation Pain