C
- Caesarean section
- Cancer
- Carbon monoxide poisoning
- Carcinoembryonic antigen (CEA) test
- Cardiac catheterisation and coronary angiography
- Cardiomyopathy
- Cardiovascular disease
- Carotid endarterectomy
- Carpal tunnel syndrome
- Cartilage damage
- Cataract surgery
- Catarrh
- Cavernoma
- Cavernous sinus thrombosis
- Cellulitis
- Cerebral palsy
- Cervical cancer
- Cervical rib
- Cervical screening
- Cervical spondylosis
- Charcot-Marie-Tooth disease
- Charles Bonnet syndrome
- Chemotherapy
- Chest infection
- Chest pain
- Chiari malformation
- Chickenpox
- Chilblains
- Childhood cataracts
- Chipped, broken or cracked tooth
- Chiropractic
- Chlamydia
- Cholera
- Cholesteatoma
- Chorionic villus sampling
- Chronic fatigue syndrome (CFS/ME)
- Chronic kidney disease
- Chronic lymphocytic leukaemia
- Chronic myeloid leukaemia
- Chronic obstructive pulmonary disease (COPD)
- Chronic pancreatitis
- Chronic traumatic encephalopathy
- Circumcision in boys
- Circumcision in men
- Cirrhosis
- Claustrophobia
- Cleft lip and palate
- Clinical depression
- Clinical trials
- Clostridium difficile
- Club foot
- Cluster headaches
- Coccydynia (tailbone pain)
- Coeliac disease
- Cognitive behavioural therapy (CBT)
- Cold sores
- Colic
- Colonoscopy
- Colostomy
- Colour vision deficiency (colour blindness)
- Colposcopy
- Coma
- Common cold
- Compartment syndrome
- Complementary and alternative medicine
- Complex regional pain syndrome
- Concussion
- Congenital heart disease
- Conjunctivitis
- Consent to treatment
- Constipation
- Contact dermatitis
- Cornea transplant
- Corns and calluses
- Coronary angioplasty and stent insertion
- Coronary artery bypass graft
- Coronary heart disease
- Coronavirus (COVID-19)
- Corticobasal degeneration
- Cosmetic procedures
- Costochondritis
- Cough
- Coughing up blood (blood in phlegm)
- Counselling
- Cradle cap
- Craniosynostosis
- Creutzfeldt-Jakob disease
- Crohn's disease
- Croup
- CT scan
- Cushing's syndrome
- Cuts and grazes
- Cyclical vomiting syndrome
- Cyclospora
- Cyclothymia
- Cystic fibrosis
- Cystitis
- Cystoscopy
- Cytomegalovirus (CMV)