This list includes 42 Diseases that start with C, from “COVID-19” to “Cytomegalovirus Infection”. It covers infectious, genetic, autoimmune, and chronic conditions and suits quick reference or introductory study.
Diseases that start with C are human medical conditions whose names begin with the letter C. Notable examples include COVID-19, which reshaped public health and global disease awareness.
Below you’ll find the table with Disease, Symptoms, Causes & Risk Factors, Treatments, and Sources.
Disease: The official, commonly used name for each condition, so you can locate and recognize entries quickly.
Symptoms: Two to four key signs or complaints that commonly appear, helping you recognize typical presentations quickly.
Causes & Risk Factors: Primary causes and the most common risk factors summarized in one line to show likely origins.
Treatments: First-line or typical treatment options and practical care steps, plus when you might seek specialist referral.
Sources: Authoritative links and references so you can read more and confirm clinical details when needed.
Diseases that start with C
| Disease | ICD-10/ICD-11 & common synonyms | Key symptoms | Primary causes & risk factors |
|---|---|---|---|
| Candidiasis | B37; Thrush, Yeast infection | White patches in mouth, skin rash and itching, vaginal discharge | Overgrowth of Candida yeast; weakened immune system, antibiotic use, diabetes. |
| Carpal Tunnel Syndrome | G56.0 | Numbness or tingling in hand/fingers, hand weakness, wrist pain | Pressure on the median nerve in the wrist; repetitive hand motions, pregnancy, genetics. |
| Cataracts | H25-H26 | Cloudy or blurry vision, fading colors, glare or halos around lights | Clouding of the eye’s lens; aging, diabetes, smoking, sun exposure. |
| Celiac Disease | K90.0; Gluten-sensitive enteropathy | Diarrhea, abdominal pain, bloating, unintended weight loss | Autoimmune reaction to gluten; family history of the disease, type 1 diabetes. |
| Cellulitis | L03 | Red, swollen, warm, and tender area of skin | Bacterial infection (Staphylococcus/Streptococcus); skin breaks, lymphedema, obesity. |
| Cerebral Palsy | G80 | Impaired movement, abnormal reflexes, floppy or rigid limbs, involuntary motions | Abnormal brain development or damage before, during, or shortly after birth. |
| Cervical Cancer | C53 | Abnormal vaginal bleeding, pelvic pain, pain during intercourse | Persistent infection with high-risk human papillomavirus (HPV); smoking, weakened immunity. |
| Chickenpox | B01; Varicella | Itchy blister-like rash all over body, fever, tiredness | Varicella-zoster virus (VZV) infection; highly contagious through air and direct contact. |
| Chikungunya | A92.0 | Sudden high fever, severe joint pain, headache, rash | Chikungunya virus; transmitted by infected Aedes mosquitoes. |
| Chlamydia | A56 | Often asymptomatic, painful urination, abnormal discharge, lower abdominal pain | Chlamydia trachomatis bacteria; sexually transmitted infection (STI). |
| Cholangitis | K83.0 | Fever, abdominal pain, yellow skin or eyes (jaundice) | Bacterial infection of the bile ducts, usually due to a blockage like a gallstone. |
| Cholecystitis | K81 | Severe pain in upper right abdomen, fever, nausea, bloating | Inflammation of the gallbladder, most often caused by gallstones blocking the cystic duct. |
| Cholera | A00 | Severe watery diarrhea, vomiting, dehydration, leg cramps | Vibrio cholerae bacteria; ingestion of contaminated food or water. |
| Chronic Fatigue Syndrome | G93.3; Myalgic Encephalomyelitis (ME/CFS) | Severe fatigue not improved by rest, post-exertional malaise, cognitive difficulties, pain | Unknown cause; potential triggers include viral infections, immune dysfunction, stress. |
| Chronic Kidney Disease | N18; CKD | Often no early symptoms; fatigue, swelling in legs, changes in urination frequency | Gradual loss of kidney function over time; diabetes and high blood pressure are main causes. |
| Chronic Obstructive Pulmonary Disease | J44; COPD | Shortness of breath, chronic cough, wheezing, excessive mucus | Long-term exposure to lung irritants, primarily cigarette smoke. |
| Cirrhosis | K74 | Fatigue, easy bruising or bleeding, jaundice, fluid retention (ascites) | Late-stage scarring (fibrosis) of the liver; chronic alcohol abuse, hepatitis C. |
| Cleft Lip and Palate | Q35-Q37 | Physical split in the upper lip and/or roof of the mouth | Congenital condition where facial tissues don’t fuse properly during fetal development. |
| Cluster Headache | G44.0 | Excruciating one-sided eye pain, eye watering, nasal congestion | Unknown cause; related to the brain’s hypothalamus. Smoking is a major risk factor. |
| Clostridium difficile Infection | A04.7; C. diff | Watery diarrhea, abdominal cramping, fever, nausea | Overgrowth of C. difficile bacteria in the colon, often after antibiotic use. |
| Colitis | K51-K52; (see also Ulcerative Colitis, Crohn’s Disease) | Diarrhea, abdominal pain, rectal bleeding, urgent need to defecate | Inflammation of the colon’s inner lining; causes include infection, IBD, ischemia. |
| Colorectal Cancer | C18-C20; Colon cancer, Rectal cancer | Change in bowel habits, blood in stool, persistent abdominal discomfort | Uncontrolled cell growth in the colon or rectum; age, polyps, family history. |
| Common Cold | J00; Acute nasopharyngitis | Runny or stuffy nose, sore throat, cough, sneezing | Viral infection of the nose and throat, most often rhinovirus. |
| Compartment Syndrome | T79.A | Severe pain out of proportion to injury, tightness in muscle, numbness | Increased pressure within a muscle compartment, often after a severe injury like a fracture. |
| Concussion | S06.0; Mild traumatic brain injury | Headache, confusion, temporary memory loss, dizziness | A blow or jolt to the head that disrupts normal brain function. |
| Congenital Heart Disease | Q20-Q26 | Abnormal heart rhythm, blue-tinged skin (cyanosis), shortness of breath during feeding | A structural problem with the heart present at birth. |
| Congestive Heart Failure | I50; Heart Failure | Shortness of breath, fatigue, swelling (edema) in legs and feet | Heart can’t pump blood effectively; hypertension and coronary artery disease are key causes. |
| Conjunctivitis | H10; Pink eye | Redness in the eye, itchiness, gritty feeling, discharge | Viral or bacterial infection, or an allergic reaction. |
| Constipation | K59.0 | Fewer than three bowel movements a week, hard or lumpy stools, straining | Slow movement of stool through the colon; inadequate fiber or fluid intake, medication. |
| Contact Dermatitis | L23-L25 | Red rash, intense itching, dry or cracked skin, blisters | Direct contact with an allergen (e.g., poison ivy) or an irritant (e.g., harsh soap). |
| Coronary Artery Disease | I25.1; CAD | Chest pain (angina), shortness of breath, heart attack | Plaque buildup (atherosclerosis) in the heart’s arteries. |
| Costochondritis | M94.0 | Sharp, aching pain in the chest wall, worse with deep breaths or coughing | Inflammation of the cartilage connecting a rib to the breastbone (sternum); cause often unknown. |
| COVID-19 | U07.1; Coronavirus disease 2019 | Fever or chills, cough, shortness of breath, new loss of taste or smell | Infection with the SARS-CoV-2 virus; spread through respiratory droplets. |
| Creutzfeldt-Jakob Disease | A81.0; CJD, a prion disease | Rapidly progressive dementia, memory loss, personality changes, muscle jerks | Abnormal infectious proteins called prions that destroy brain cells. |
| Crohn’s Disease | K50 | Diarrhea, abdominal cramps and pain, weight loss, rectal bleeding | A type of inflammatory bowel disease (IBD); likely from immune system dysfunction. |
| Croup | J05.0; Laryngotracheobronchitis | Barking cough, hoarse voice, noisy breathing (stridor) | Viral infection of the upper airway, most common in young children. |
| Cushing’s Syndrome | E24 | Weight gain in face and upper back, purple stretch marks, high blood pressure | Prolonged exposure to high levels of the hormone cortisol, often from steroid drugs or tumors. |
| Cyclic Vomiting Syndrome | G43.A; CVS | Recurrent, severe episodes of nausea and vomiting lasting for hours or days | Unknown cause; often associated with migraines. Triggers can include stress or excitement. |
| Cyclothymia | F34.0; Cyclothymic disorder | Numerous periods of hypomanic and depressive symptoms that are not severe enough for bipolar disorder | Exact cause unknown; genetics, brain chemistry, and environment likely play a role. |
| Cystic Fibrosis | E84 | Persistent cough with thick mucus, frequent lung infections, poor growth, very salty skin | Genetic disorder affecting the CFTR protein; inherited from parents. |
| Cystitis | N30; Bladder infection | Frequent urge to urinate, burning sensation with urination, cloudy or bloody urine | Bacterial infection of the bladder, a common type of urinary tract infection (UTI). |
| Cytomegalovirus Infection | B25; CMV | Often asymptomatic; fever, sore throat, fatigue in healthy people | Common herpesvirus; spread through direct contact with infected body fluids. |
Descriptions
Candidiasis
A fungal infection affecting skin, mouth, or genital areas. Treated with antifungal creams or oral medications. See a doctor for persistent or severe symptoms.
Carpal Tunnel Syndrome
A common condition causing pain and numbness in the hand. Management includes wrist splints, steroid injections, and sometimes surgery. A neurologist may be consulted.
Cataracts
A progressive clouding of the eye’s natural lens, impairing vision. The main treatment is surgery to replace the cloudy lens with a clear artificial one. See an ophthalmologist.
Celiac Disease
An autoimmune disorder where eating gluten damages the small intestine. The only treatment is a lifelong, strict gluten-free diet. A gastroenterologist manages this condition.
Cellulitis
A common bacterial skin infection that can become serious. It is treated with oral or intravenous antibiotics. Seek medical care promptly to prevent the infection from spreading.
Cerebral Palsy
A group of disorders affecting movement, balance, and posture. Lifelong management involves physical therapy, medications, and other support. A team of specialists is usually involved.
Cervical Cancer
Cancer that occurs in the cells of the cervix. Preventable with HPV vaccination and detectable early with screening tests. Treatment includes surgery, radiation, and chemotherapy.
Chickenpox
A highly contagious viral infection common in children. Treatment is supportive care to relieve symptoms. The chickenpox vaccine is highly effective at preventing the disease.
Chikungunya
A viral illness transmitted by mosquitoes, causing fever and severe joint pain. There is no specific cure; treatment focuses on relieving symptoms with rest, fluids, and pain relievers.
Chlamydia
A very common bacterial STI that can cause serious reproductive health problems if untreated. It is easily cured with a short course of antibiotics.
Cholangitis
Inflammation of the bile duct system, which is a serious and potentially life-threatening infection. Requires urgent treatment with antibiotics and a procedure to drain the bile duct.
Cholecystitis
A painful inflammation of the gallbladder. Treatment often involves hospitalization for IV fluids, antibiotics, and surgical removal of the gallbladder (cholecystectomy).
Cholera
An acute diarrheal illness that can cause severe dehydration and be fatal if not treated. Treatment involves immediate rehydration with oral or IV fluids and antibiotics.
Chronic Fatigue Syndrome
A complex, long-term illness causing extreme fatigue that interferes with daily activities. Management focuses on symptom relief and activity pacing. A specialist may be needed.
Chronic Kidney Disease
A progressive condition where kidneys lose function. Treatment aims to slow progression by managing the underlying cause. See a nephrologist (kidney specialist) for management.
Chronic Obstructive Pulmonary Disease
A group of lung diseases including emphysema and chronic bronchitis that block airflow. Management includes inhalers, steroids, and oxygen therapy. See a pulmonologist.
Cirrhosis
An irreversible liver condition where scar tissue replaces healthy tissue, impairing function. Treatment manages symptoms and underlying causes. A hepatologist (liver specialist) guides care.
Cleft Lip and Palate
Birth defects affecting the upper lip and roof of the mouth. Treatment requires a series of surgeries and a team of specialists for feeding, speech, and dental care.
Cluster Headache
A neurological disorder causing recurrent, severe headaches on one side of the head. Acute treatment involves high-flow oxygen or triptan medications. A neurologist can help manage this.
Clostridium difficile Infection
A bacterium that can cause swelling and irritation of the large intestine, or colon. It is treated with specific antibiotics. Severe cases may require hospitalization.
Colitis
Inflammation of the large intestine. Treatment depends on the underlying cause but may include anti-inflammatory drugs or antibiotics. A gastroenterologist is often consulted.
Colorectal Cancer
Cancer of the large intestine. Regular screening is crucial for early detection. Treatment includes surgery, chemotherapy, and radiation, managed by an oncologist.
Common Cold
A mild, self-limiting viral infection of the upper respiratory tract. There is no cure; treatment is supportive with rest, fluids, and over-the-counter medications.
Compartment Syndrome
A medical emergency caused by pressure buildup from swelling or bleeding. It requires urgent surgery (fasciotomy) to relieve pressure and prevent permanent muscle or nerve damage.
Concussion
A type of traumatic brain injury. The primary treatment is physical and cognitive rest to allow the brain to heal. Symptoms usually resolve within a few weeks.
Congenital Heart Disease
A general term for a range of birth defects affecting the heart’s structure. Treatment can range from monitoring to medication or surgery. A pediatric cardiologist manages care.
Congestive Heart Failure
A chronic condition where the heart muscle is weakened. Management includes lifestyle changes, medications (like diuretics and ACE inhibitors), and sometimes devices. See a cardiologist.
Conjunctivitis
Inflammation of the membrane lining the eyelid and eyeball. Treatment depends on the cause, ranging from supportive care to antibiotic or allergy eye drops.
Constipation
A common condition characterized by infrequent or difficult bowel movements. First-line treatment includes increasing dietary fiber, fluid intake, and exercise.
Contact Dermatitis
A type of skin inflammation caused by external substances. Treatment involves avoiding the trigger and using steroid creams or oral medications to reduce the rash. See a dermatologist.
Coronary Artery Disease
The most common type of heart disease, caused by narrowed arteries. Treatment includes lifestyle changes, medications, angioplasty, or bypass surgery. A cardiologist manages care.
Costochondritis
A common cause of chest pain that is typically harmless. Treatment focuses on pain relief with anti-inflammatory drugs and rest. Usually resolves on its own.
COVID-19
A contagious respiratory disease with a wide range of symptoms. Treatment is supportive for mild cases and may include antiviral drugs or hospitalization for severe illness.
Creutzfeldt-Jakob Disease
A rare, degenerative, and fatal brain disorder. There is no cure, and treatment is focused on supportive care to relieve symptoms. A neurologist is consulted for diagnosis.
Crohn’s Disease
A chronic inflammatory condition affecting the digestive tract. Treatment aims to reduce inflammation and includes medications, diet changes, and sometimes surgery. See a gastroenterologist.
Croup
An infection causing swelling around the vocal cords. Mild cases are treated at home with cool, humid air. Severe cases may require steroids or hospitalization.
Cushing’s Syndrome
A hormonal disorder caused by excess cortisol. Treatment depends on the cause and aims to lower cortisol levels via medication, surgery, or radiation. An endocrinologist manages care.
Cyclic Vomiting Syndrome
A disorder characterized by episodes of severe vomiting with no apparent cause. Treatment focuses on preventing episodes and supportive care during them. See a gastroenterologist.
Cyclothymia
A milder form of bipolar disorder involving chronic, fluctuating moods. Treatment typically involves psychotherapy and sometimes mood-stabilizing medications. A psychiatrist can diagnose and manage.
Cystic Fibrosis
A progressive genetic disease causing persistent lung infections and digestive problems. Management is complex and requires lifelong care at a specialized CF center.
Cystitis
Inflammation of the bladder. It is a common infection, especially in women, and is typically treated with a short course of oral antibiotics prescribed by a doctor.
Cytomegalovirus Infection
A common virus that rarely causes issues in healthy people but can be serious for those with weak immune systems or for babies infected before birth. Antiviral medication may be used.