Here you’ll find 36 Diseases that start with H that begin with H, organized from “HIV/AIDS” to “Hypothyroidism”. They range from infectious and immune disorders to common endocrine and metabolic conditions, including several major global health concerns.
Diseases that start with H are a varied group of medical conditions affecting many body systems. For example, HIV/AIDS changed global public health and still shapes research and care worldwide.
Below you’ll find the table with [COLUMN_NAMES].
Disease: The official name of the condition, helping you identify and match it to clinical terms and further resources.
Symptoms: Typical signs and symptoms condensed to two to four key points so you quickly recognize common presentations.
Causes: Primary causes and top risk factors summarized in one to two lines to explain likely origins or mechanisms.
Treatments: First-line and typical treatment options listed, plus a brief referral note when specialist care is generally recommended.
Notes: Brief clinical tips, prevalence or severity cues that help you prioritize further reading or action.
Clinician review: Indicates whether an entry has been reviewed by a healthcare professional for accuracy and clinical relevance.
Sources: Links to major references and guidelines let you follow up with authoritative materials and original descriptions.
Diseases that start with H
| Name | ICD-10/ICD-11 Code(s) | Key symptoms | Main causes / risk factors |
|---|---|---|---|
| Haemophilia | D66; D67 | Prolonged bleeding, easy bruising, joint pain and swelling | Genetic disorder impairing blood clotting |
| Hand, foot, and mouth disease | B08.4 | Fever, sore throat, rash on hands and feet, mouth sores | Enterovirus infection, common in young children |
| Hantavirus pulmonary syndrome | B33.4; J17.0 | Fever, muscle aches, shortness of breath, cough | Inhaling dust from infected rodent droppings or urine |
| Hashimoto’s thyroiditis | E06.3 | Fatigue, weight gain, cold intolerance, goiter | Autoimmune attack on the thyroid gland |
| Hay fever | J30.1 | Sneezing, runny nose, itchy eyes, nasal congestion | Allergic reaction to airborne pollen, dust mites, or pet dander |
| Head and neck cancer | C00-C14; C30-C32 | A sore that does not heal, difficulty swallowing, voice changes | Tobacco use, heavy alcohol consumption, HPV infection |
| Heart attack | I21-I22 | Chest pain or pressure, shortness of breath, pain in arm or jaw | Blocked blood flow to the heart muscle, atherosclerosis |
| Heart failure | I50 | Shortness of breath, fatigue, swollen legs or ankles | Weakened or stiff heart muscle; coronary artery disease, high blood pressure |
| Heat stroke | T67.0 | High body temperature, confusion, flushed skin, no sweating | Prolonged exposure to high temperatures, physical exertion in heat |
| Hemochromatosis | E83.1 | Fatigue, joint pain, abdominal pain, weakness | Genetic mutations causing excessive iron absorption from food |
| Hemolytic uremic syndrome (HUS) | D59.3 | Bloody diarrhea, low urine output, fatigue, pale skin | Often follows E. coli infection; certain medications, genetic factors |
| Hemorrhoids | K64; I84 | Anal itching, pain or discomfort, bleeding during bowel movements | Straining during bowel movements, chronic constipation, pregnancy |
| Hepatitis A | B15 | Jaundice, fatigue, nausea, abdominal pain | Hepatitis A virus (HAV), usually from contaminated food or water |
| Hepatitis B | B16; B18.0; B18.1 | Jaundice, fatigue, dark urine, abdominal pain | Hepatitis B virus (HBV), spread through blood or bodily fluids |
| Hepatitis C | B17.1; B18.2 | Fatigue, jaundice, poor appetite, joint pain | Hepatitis C virus (HCV), primarily spread through contact with infected blood |
| Hepatocellular carcinoma | C22.0 | Abdominal pain, unexplained weight loss, jaundice, swelling | Chronic hepatitis B or C infection, cirrhosis, heavy alcohol use |
| Herniated disc | M50.2; M51.2 | Sharp pain in arm or leg, numbness or tingling, muscle weakness | Age-related wear and tear (disc degeneration), sudden strain |
| Herpes simplex virus (HSV) infection | B00; A60 | Painful sores or blisters on the mouth, genitals, or rectum | Herpes simplex virus type 1 (HSV-1) or type 2 (HSV-2) |
| Herpes zoster (Shingles) | B02 | Painful, blistering rash on one side of the body, tingling, fever | Reactivation of the varicella-zoster virus (chickenpox virus) |
| Hiatal hernia | K44.9 | Heartburn, acid reflux, chest pain, difficulty swallowing | Part of the stomach pushes up through the diaphragm muscle |
| Hidradenitis suppurativa | L73.2 | Painful, recurring lumps under the skin, blackheads, tunnels under skin | Blocked hair follicles; genetic and hormonal factors |
| Hirschsprung’s disease | Q43.1 | Failure to pass stool in newborns, swollen belly, vomiting | Congenital absence of nerve cells in the colon |
| Histoplasmosis | B39 | Fever, cough, fatigue, chest pain | Inhaling spores of the fungus Histoplasma, found in bird/bat droppings |
| Hives (Urticaria) | L50 | Itchy, raised, red or skin-colored welts (wheals) | Allergic reactions, infections, stress, medications |
| HIV/AIDS | B20-B24 | Flu-like symptoms initially, weight loss, recurrent infections | Human immunodeficiency virus (HIV) attacking the immune system |
| Hoarding disorder | F42.3; 6B24 | Difficulty discarding possessions, cluttered living spaces, distress | Complex; genetic, brain functioning, and stressful life events |
| Hodgkin’s lymphoma | C81 | Painless swelling of lymph nodes, fever, night sweats, weight loss | Cancer of the lymphatic system; Epstein-Barr virus, family history |
| Human papillomavirus (HPV) infection | B97.7; A63.0 | Often no symptoms; can cause genital warts or certain cancers | Infection with the human papillomavirus, a common sexually transmitted virus |
| Huntington’s disease | G10 | Involuntary jerking movements, cognitive decline, mood swings | An inherited genetic defect on a single gene |
| Hydrocephalus | G91 | Enlarged head (in infants), headache, nausea, vision problems | Buildup of cerebrospinal fluid (CSF) within the brain |
| Hypercholesterolemia (High cholesterol) | E78.0 | No symptoms; detected by blood test | Diet high in saturated fats, physical inactivity, genetics, obesity |
| Hypertension (High blood pressure) | I10-I16 | Usually no symptoms; sometimes headaches or dizziness | Genetics, age, diet high in salt, obesity, lack of exercise |
| Hyperthyroidism | E05 | Unexplained weight loss, rapid or irregular heartbeat, anxiety | Overproduction of thyroid hormone; Graves’ disease, thyroid nodules |
| Hypertrophic cardiomyopathy | I42.1; I42.2 | Chest pain, shortness of breath, fainting, heart palpitations | Genetic mutations causing the heart muscle to become abnormally thick |
| Hypoglycemia (Low blood sugar) | E16.2 | Shakiness, sweating, confusion, rapid heartbeat | Too much insulin or diabetes medication, not eating enough |
| Hypothyroidism | E00-E03 | Fatigue, weight gain, feeling cold, depression, dry skin | Underactive thyroid gland; Hashimoto’s disease, iodine deficiency |
Descriptions
Haemophilia
A rare, inherited disorder where the blood doesn’t clot properly, leading to excessive bleeding after injury or surgery. It primarily affects males. Treatment involves replacing the missing clotting factor.
Hand, foot, and mouth disease
A common and contagious viral illness that typically affects infants and children under 5. It is usually mild and resolves on its own within a week to 10 days.
Hantavirus pulmonary syndrome
A rare but severe and often fatal respiratory disease caused by hantaviruses. Immediate medical attention is crucial as it can progress rapidly to respiratory failure.
Hashimoto’s thyroiditis
An autoimmune disorder that is the most common cause of hypothyroidism (underactive thyroid). The immune system attacks the thyroid, impairing its ability to produce hormones. Lifelong hormone therapy is the standard treatment.
Hay fever
Also known as allergic rhinitis, this is a very common allergic condition causing cold-like symptoms. It can be seasonal or year-round and is managed with antihistamines and nasal sprays.
Head and neck cancer
A group of cancers that start in the mouth, throat, sinuses, or larynx. Early detection is key for successful treatment, which may include surgery, radiation, and chemotherapy.
Heart attack
A life-threatening medical emergency where a coronary artery is blocked, damaging the heart muscle. Immediate emergency care is critical to restore blood flow and save heart tissue.
Heart failure
A chronic condition where the heart cannot pump blood effectively. It is a serious, progressive disease that requires ongoing medical management to control symptoms and improve quality of life.
Heat stroke
The most serious form of heat injury and a medical emergency. The body’s temperature regulation fails, leading to a dangerously high core temperature. Immediate cooling and medical care are vital.
Hemochromatosis
A genetic disorder that causes the body to absorb too much iron, which builds up in organs like the liver, heart, and pancreas, causing damage. Treatment involves removing excess iron from the blood.
Hemolytic uremic syndrome (HUS)
A serious condition where damaged red blood cells clog the filtering system in the kidneys, leading to kidney failure. It most commonly affects young children and requires hospitalization.
Hemorrhoids
Swollen and inflamed veins in the rectum and anus. They are very common and often can be managed with lifestyle changes and over-the-counter remedies. Severe cases may require medical procedures.
Hepatitis A
A highly contagious liver infection that is preventable by vaccine. It typically causes a short-term illness and does not lead to chronic liver disease. Most people recover fully.
Hepatitis B
A serious liver infection that can become chronic, increasing the risk of liver failure, cancer, or cirrhosis. A vaccine is available for prevention. Antiviral medications can treat chronic infection.
Hepatitis C
A viral liver infection that often becomes chronic and can lead to serious liver damage over many years. Many people are asymptomatic. Effective antiviral drugs can now cure most infections.
Hepatocellular carcinoma
The most common type of primary liver cancer. It often develops in people with chronic liver diseases. Treatment depends on the stage and may include surgery, transplant, or chemotherapy.
Herniated disc
A condition where the soft, gel-like center of a spinal disc pushes through a tear in the tougher exterior. It commonly causes back or neck pain and nerve-related symptoms.
Herpes simplex virus (HSV) infection
A very common and contagious viral infection that causes sores, most often around the mouth (cold sores) or on the genitals. The virus remains in the body for life, with periodic outbreaks.
Herpes zoster (Shingles)
A viral infection that causes a painful rash. It occurs in people who have had chickenpox, as the virus can lie dormant and reactivate later in life. A vaccine is available for older adults.
Hiatal hernia
A common condition where the upper part of the stomach bulges through an opening in the diaphragm. Small hernias may cause no problems, while large ones can lead to significant reflux and discomfort.
Hidradenitis suppurativa
A chronic, inflammatory skin disease that causes painful lumps, abscesses, and scarring in areas like the armpits, groin, and buttocks. It is not contagious but can be very distressing.
Hirschsprung’s disease
A birth defect affecting the large intestine, which prevents proper stool movement. It is diagnosed in infancy and requires surgery to remove the affected portion of the colon.
Histoplasmosis
A fungal infection that primarily affects the lungs. Most cases are mild and resolve without treatment, but it can become severe, especially in people with weakened immune systems.
Hives (Urticaria)
A common skin reaction that causes itchy welts. Acute hives appear suddenly and clear up within a few weeks, while chronic hives can last for months or years. Antihistamines are the main treatment.
HIV/AIDS
A virus that attacks the body’s immune cells. If untreated, it can lead to acquired immunodeficiency syndrome (AIDS). With modern antiretroviral therapy (ART), people with HIV can live long, healthy lives.
Hoarding disorder
A persistent difficulty getting rid of possessions because of a perceived need to save them. It can lead to unsafe living conditions and requires professional psychological treatment.
Hodgkin’s lymphoma
A type of cancer that originates in white blood cells called lymphocytes. It is one of the most curable forms of cancer, especially when diagnosed and treated early.
Human papillomavirus (HPV) infection
The most common sexually transmitted infection. Most HPV infections cause no symptoms and resolve on their own, but some persistent types can lead to cancers, notably cervical cancer. Vaccines are highly effective.
Huntington’s disease
A progressive, fatal brain disorder that causes uncontrolled movements, emotional problems, and loss of thinking ability. There is no cure, but treatments can help manage symptoms.
Hydrocephalus
A condition characterized by an abnormal accumulation of fluid in the brain, increasing pressure. It can be present at birth or acquired later. Treatment usually involves surgically inserting a shunt to drain excess fluid.
Hypercholesterolemia (High cholesterol)
A condition where there is too much cholesterol, a waxy substance, in the blood. It contributes to atherosclerosis, significantly increasing the risk of heart attack and stroke. It’s managed with lifestyle changes and medication.
Hypertension (High blood pressure)
A common condition where the long-term force of the blood against artery walls is high enough to cause health problems, such as heart disease. It is often called the “silent killer.”
Hyperthyroidism
A condition where the thyroid gland produces too much thyroxine hormone. This accelerates the body’s metabolism, causing a wide range of symptoms. Treatment aims to lower thyroid hormone levels.
Hypertrophic cardiomyopathy
An inherited heart disease where the heart muscle thickens, making it harder for the heart to pump blood. It is a leading cause of sudden cardiac death in young athletes.
Hypoglycemia (Low blood sugar)
A condition characterized by an abnormally low level of blood sugar (glucose). It is most common in people with diabetes but can have other causes. Prompt treatment with sugar is needed.
Hypothyroidism
A common condition where the thyroid gland doesn’t produce enough crucial hormones. It slows down the body’s metabolism. Treatment involves daily use of a synthetic thyroid hormone medication.