In-depth

Acromegaly

Acute kidney injury

Acute lymphocytic leukemia

Acute myelogenous leukemia

Acute sinusitis

Addison's disease

Alpha-1-antitrypsin deficiency

Amyloidosis

Anaphylaxis

Anemia

Angina

Anorexia nervosa

Anthrax

Anxiety disorders

Aortic valve regurgitation

Aortic valve stenosis

Aplastic anemia

ARDS

Arteriovenous fistula

Ascariasis

Aspergillosis

Astrocytoma

Atrial septal defect (ASD)

Atrioventricular canal defect

Autoimmune hepatitis

B-cell lymphoma

Bipolar disorder

Blastocystis hominis

Bone cancer

Bradycardia

Brain tumor

Bronchitis

Brucellosis

Brugada syndrome

Burkitt lymphoma

Cancer

Cardiomyopathy

Castleman disease

Celiac disease

Chagas disease

Chemo brain

Cholangiocarcinoma (bile duct cancer)

Cholera

Chronic kidney disease

Chronic lymphocytic leukemia

Chronic myelogenous leukemia

Chronic sinusitis

Churg-Strauss syndrome

Colon cancer

Common cold

Concussion

Crohn's disease

Cushing syndrome

Cyclothymia (cyclothymic disorder)

Dermatomyositis

Diabetes

Diabetes affects how your body uses blood sugar. Too much blood sugar over long periods can cause serious health problems, but treatments are available.

Diabetic coma

Diabetic ketoacidosis

Diffuse large B-cell lymphoma

Diffuse midline glioma (DMG)

Dilated cardiomyopathy

Dumping syndrome

Ebstein anomaly

Encephalitis

Endocarditis

Endometriosis

Enlarged liver

Enlarged spleen (splenomegaly)

Esophageal cancer

Ewing sarcoma

Fibromyalgia

Follicular lymphoma

Gaucher disease

Generalized anxiety disorder

Giardia infection (giardiasis)

Glomerulonephritis

Granulomatosis with polyangiitis

Graves' disease

H1N1 flu (swine flu)

Hairy cell leukemia

Hangovers

Hashimoto's disease

Heart arrhythmia

Heart attack

Heart disease

Heart failure

Heat exhaustion

Heavy menstrual bleeding

Hemolytic uremic syndrome (HUS)

Hemophilia

Hepatitis A

Hepatitis B

Hepatitis C

Hiatal hernia

Hilar cholangiocarcinoma

Hirschsprung's disease

HIV/AIDS

Huntington's disease

Hypercalcemia

Hyperglycemia in diabetes

Hyperparathyroidism

Hyperthyroidism (overactive thyroid)

Hypertrophic cardiomyopathy

Hyponatremia

Hypoparathyroidism

Hypopituitarism

Hypothermia

Hypothyroidism (underactive thyroid)

Inflammatory bowel disease (IBD)

Influenza (flu)

Insomnia

Iron deficiency anemia

Jet lag disorder

Kidney cancer

Lead poisoning

Legionnaires' disease

Leukemia

Listeria infection

Liver cancer

Liver disease

Long QT syndrome

Low blood pressure (hypotension)

Lupus

Lyme disease

Lymphoma

Male hypogonadism

Mantle cell lymphoma

Medulloblastoma

Membranous nephropathy

Mental illness

Metastatic (stage 4) prostate cancer

Metastatic castration-resistant prostate cancer (mCRPC)

Mitral valve prolapse

Mitral valve regurgitation

Mitral valve stenosis

Mixed connective tissue disease

Mononucleosis

Multiple myeloma

Multiple sclerosis

Multisystem inflammatory syndrome in children (MIS-C)

Mumps

Myelodysplastic syndromes

Myelofibrosis

Myocarditis

Pancreatic neuroendocrine tumors

Parvovirus infection

Pectus excavatum

Pelvic inflammatory disease (PID)

Pericarditis

Peritoneal carcinomatosis

Peritonitis

Persistent depressive disorder

Persistent post-concussive symptoms (Post-concussion syndrome)

Pineal gland tumor

Pituitary tumors and adenomas

Plague

Pneumonia

Pneumonitis

Polio

One of the most feared diseases of the 20th century, polio has been eradicated from the developed world but remains a threat in less developed nations.

Polycythemia vera

Polymyalgia rheumatica

Post COVID syndrome

Postpartum depression

Post-polio syndrome

Prediabetes

Premenstrual syndrome (PMS)

Primary biliary cholangitis (PBC)

Primary mediastinal large B-cell lymphoma

Primary sclerosing cholangitis (PSC)

Prostate cancer recurrence

Pulmonary atresia

Pulmonary atresia with intact ventricular septum

Pulmonary edema

Pulmonary fibrosis

Pulmonary hypertension

Pulmonary valve stenosis

Rectal cancer

Rheumatic fever

Rheumatoid arthritis

Roseola

Sarcoidosis

Sheehan's syndrome

Shingles

Sick sinus syndrome

Sinus headaches

Sjogren's syndrome

Small vessel disease

Smallpox

Somatic symptom disorder

Stomach cancer

Strep throat

Sudden cardiac arrest

Sunburn

Takayasu's arteritis

T-cell lymphoma

Teen depression

Thalassemia

Tonic-clonic (grand mal) seizure

Toxic hepatitis

Toxoplasmosis

Tricuspid atresia

Tricuspid valve regurgitation

Tuberculosis

Type 1 diabetes

Type 1 diabetes in children

Type 2 diabetes

Type 2 diabetes in children

Typhoid fever

Ulcerative colitis

Valley fever

Vasculitis

Ventricular septal defect (VSD)

VEXAS syndrome

Viral hemorrhagic fevers

Vitamin deficiency anemia

West Nile virus

Whiplash

Whipple's disease

Whooping cough

Wilson's disease

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Feb. 20, 2026

See also

  1. ​Grade 4 brain cancer: what to expect, treatment options and support
  2. ​Self-care for fatty liver disease (MASLD)
  3. 6 tips to manage rheumatoid arthritis symptoms
  4. A leaky tricuspid valve
  5. Acute lymphocytic leukemia
  6. Acute sinusitis
  7. Acute sinusitis: Do over-the-counter treatments help?
  8. Addison's disease
  9. Adenocarcinoma: How this type of cancer affects prognosis
  10. Amyloidosis
  11. Anaphylaxis: First aid
  12. Anemia
  13. Angina
  14. Anorexia nervosa
  15. Anthrax
  16. Antidepressants and weight gain: What causes it?
  17. Antidepressants: Can they stop working?
  18. Anxiety and diet
  19. Anxiety disorders
  20. Aortic calcification: An early sign of heart valve problems?
  21. Aortic valve regurgitation
  22. Aortic valve stenosis
  23. ARDS
  24. Artificial sweeteners: Any effect on blood sugar?
  25. Ascariasis
  26. Aspergillosis
  27. At-home colon cancer tests
  28. Atrial septal defect (ASD)
  29. Atypical antidepressants
  30. Biliary tract cancer: Should I get a second opinion?
  31. Bipolar disorder
  32. Bipolar disorder and alcoholism: Are they related?
  33. Bipolar disorder in children: Is it possible?
  34. Blastocystis hominis
  35. Blood sugar testing: Why, when and how
  36. Blood tests for heart disease
  37. Bone cancer
  38. Brain tumor
  39. Can seasonal and life changes trigger ulcerative colitis flares?
  40. Can vitamins help prevent a heart attack?
  41. Cancer blood tests: Lab tests used in cancer diagnosis
  42. Cancer causes: Popular myths about the causes of cancer
  43. Cancer fatigue: Why it occurs and how to cope
  44. Cancer pain: Relief is possible
  45. Cancer survival rate: What it means for your prognosis
  46. Cardiac asthma: What causes it?
  47. Celiac disease
  48. Chelation therapy for heart disease: Does it work?
  49. Chemo brain
  50. Chronic kidney disease
  51. Chronic kidney disease: Is a clinical trial right for me?
  52. Chronic sinusitis
  53. Churg-Strauss syndrome
  54. Coconut oil: Can it cure hypothyroidism?
  55. Cold symptoms: Does drinking milk increase phlegm?
  56. Colon Cancer Family Registry
  57. Colon cancer prevention: What you can do
  58. Common cold
  59. Concussion
  60. Concussion in children
  61. Craving and chewing ice: A sign of anemia?
  62. Crohn's Crisis
  63. Crohn's disease and the gut microbiome
  64. Cutaneous B-cell lymphoma
  65. Dermatomyositis
  66. Diabetes and depression: Coping with the two conditions
  67. Diabetes and exercise: When to monitor your blood sugar
  68. Diabetes and heat
  69. Diabetes care: 10 ways to avoid complications
  70. Diabetes diet: Should I avoid sweet fruits?
  71. Diabetes foods: Can I substitute honey for sugar?
  72. Diabetes management: How lifestyle, daily routine affect blood sugar
  73. Diabetes treatment: Medications for type 2 diabetes
  74. Diabetes treatment: Using insulin to manage blood sugar
  75. Diabetic ketoacidosis
  76. Dilated cardiomyopathy
  77. Do zinc supplements shorten colds?
  78. Does stress make rheumatoid arthritis worse?
  79. Drummer Beats Heart Disease
  80. Dumping syndrome
  81. Early HIV symptoms: What are they?
  82. Ebstein anomaly
  83. ED Drugs for Pulmonary Hypertension
  84. Effectively managing chronic kidney disease
  85. Endometriosis FAQs
  86. Enlarged spleen (splenomegaly)
  87. Esophageal cancer
  88. Ewing sarcoma
  89. Explaining multiple sclerosis
  90. Fatty liver disease (MASLD) diet
  91. Fertility preservation: Understand your options before cancer treatment
  92. Fibromyalgia
  93. Flu shot: Your best bet for avoiding influenza
  94. Flu shots: Especially important if you have heart disease
  95. Flu vaccine: Safe for people with egg allergy?
  96. Follicular lymphoma
  97. Gaucher disease
  98. Genetics and Cardiomyopathy
  99. GI Stents
  100. Glycemic index: A helpful tool for diabetes?
  101. Grass-fed beef
  102. Hairy cell leukemia
  103. Healthy Heart for Life!
  104. Heart attack
  105. Heart attack prevention: Should I avoid secondhand smoke?
  106. Heart attack symptoms: Know what's a medical emergency
  107. Heart Attack Timing
  108. Heart disease
  109. Heart disease in women: Understand symptoms and risk factors
  110. Heart failure
  111. Heart failure action plan
  112. Heat exhaustion
  113. Heavy periods: Can folic acid help?
  114. Hepatitis B and Hepatitis C: What's the difference?
  115. Hepatitis C
  116. Hepatitis C screening
  117. Hepatitis C: What happens in end-stage liver disease?
  118. Herbal treatment for anxiety: Is it effective?
  119. High-dose flu vaccines: How are they different from other flu vaccines?
  120. High-dose vitamin C: Can it kill cancer cells?
  121. Hirschsprung's disease
  122. Hodgkin lymphoma (Hodgkin disease)
  123. Hodgkin vs. non-Hodgkin lymphoma: What's the difference?
  124. How do I reduce fatigue from rheumatoid arthritis?
  125. How kidneys work
  126. Hypercalcemia
  127. Hyperthyroidism (overactive thyroid)
  128. Hypertrophic cardiomyopathy
  129. Hyponatremia
  130. Hypoparathyroidism
  131. Hypopituitarism
  132. Hypothermia
  133. Hypothyroidism (underactive thyroid)
  134. Hypothyroidism and joint pain?
  135. Hypothyroidism: Can calcium supplements interfere with treatment?
  136. Influenza (flu)
  137. Infographic: Multiple Myeloma
  138. Infographic: Pancreatic Neuroendocrine Tumors
  139. Insomnia: How do I stay asleep?
  140. Insulin and weight gain: Keep the pounds off
  141. Is there a special diet for Crohn's disease?
  142. Jack Long — Live LONG - Beat STRONG to find a cure
  143. Jet lag disorder
  144. Kidney Cancer
  145. Kidney cancer FAQs
  146. Kidney disease FAQs
  147. Lack of sleep: Can it make you sick?
  148. LADA
  149. Lead poisoning
  150. Listeria infection
  151. Liver cancer
  152. Liver disease: How medications can harm the liver
  153. Long Term Brain Cancer Survivor
  154. Low blood cell counts: Side effects of cancer treatment
  155. Low blood sodium in older adults: A concern?
  156. Low-phosphorus diet: Helpful for kidney disease?
  157. Lyme disease
  158. Lymphoma FAQs
  159. Male depression: Understanding the issues
  160. Male hypogonadism
  161. Mayo Clinic Minute: Will there be a Lyme disease vaccine for humans?
  162. Medications for liver failure
  163. Medicines that treat ulcerative colitis
  164. Mental health providers: Tips on finding one
  165. Mental health: Overcoming the stigma of mental illness
  166. Mental illness
  167. Metastatic castration-resistant prostate cancer (mCRPC)
  168. Mitral valve overview
  169. Mitral valve regurgitation
  170. Multiple myeloma
  171. Multiple sclerosis FAQs
  172. Multisystem inflammatory syndrome in children (MIS-C)
  173. Mumps
  174. Myelodysplastic syndromes
  175. Natural remedies for depression: Are they effective?
  176. Neti pot: Can it clear my nose?
  177. Non-Hodgkin lymphoma
  178. NSAIDs: Do they increase my risk of heart attack and stroke?
  179. Omega-6 fatty acids
  180. Palliative care for biliary tract cancer
  181. Pancreatic neuroendocrine tumors
  182. Parvovirus infection
  183. Pericarditis
  184. Peritoneal carcinomatosis
  185. Peritonitis
  186. Petroleum jelly: Safe for a dry nose?
  187. PICC line placement
  188. Pineal gland tumor
  189. Pituitary tumors and adenomas
  190. Plague
  191. Polio
  192. Polypill: Does it treat heart disease?
  193. Postpartum depression
  194. Premenstrual dysphoric disorder
  195. Prescription sleeping pills: What's right for you?
  196. Prostate cancer recurrence
  197. Pulmonary atresia
  198. Pulmonary atresia with intact ventricular septum
  199. Pulmonary hypertension
  200. Pulmonary valve stenosis
  201. Reactive hypoglycemia: What can I do?
  202. Rectal cancer
  203. Red wine and resveratrol: Good for your heart?
  204. Rhabdomyolysis
  205. Rheumatoid arthritis
  206. Rheumatoid arthritis: Can it affect the lungs?
  207. Rheumatoid arthritis: Does pregnancy affect symptoms?
  208. Robotic heart surgery treats mitral regurgitation: Ed's story
  209. Sarcoidosis
  210. Self-care for the flu
  211. Shingles
  212. Shingles vaccine: Can I transmit the vaccine virus to others?
  213. Shingles vaccine: Should I get it?
  214. Sick sinus syndrome
  215. Silent heart attack
  216. Sinus headaches
  217. Sinus infection and toothache: Any connection?
  218. Small lymphocytic lymphoma
  219. Smallpox
  220. Test anxiety: Can it be treated?
  221. Thalassemia
  222. The dawn phenomenon: What can you do?
  223. The gut microbiome and its role in ulcerative colitis
  224. Thyroid disease: Can it affect a person's mood?
  225. Thyroid peroxidase antibody test: What is it?
  226. Tips for recovering after an ulcerative colitis flare-up
  227. Tips to make your mornings easier
  228. Treating Pericarditis
  229. Treatment options for biliary tract cancer
  230. Tricuspid valve regurgitation
  231. Tuberculosis
  232. Type 1 diabetes FAQs
  233. Type 1 diabetes in children
  234. Type 2 diabetes
  235. Typhoid fever
  236. Ulcerative colitis vs. Crohn's disease
  237. Understanding complement 3 glomerulopathy (C3G)
  238. VEXAS syndrome
  239. Video: Heart and circulatory system
  240. Video: Septal myectomy and apical myectomy
  241. Vitamin B-12 and depression
  242. Vitamin deficiency anemia
  243. Vitamins for MS: Do supplements make a difference?
  244. Von Willebrand disease
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  247. What is cirrhosis? A Mayo Clinic expert explains
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  249. What is kidney cancer? An expert explains
  250. What is kidney disease? An expert explains
  251. What is stomach cancer? A Mayo Clinic expert explains
  252. What is type 1 diabetes? A Mayo Clinic expert explains
  253. What is ulcerative colitis? A Mayo Clinic expert explains
  254. White stool: Should I be concerned?
  255. Whooping cough
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  257. Why isn't there a hepatitis C vaccine?