Recent Articles

Hemoglobin A1c (HbA1c): What to know if you have diabetes or prediabetes or are at risk for these conditions

What could be causing your blurry vision?

Avocado nutrition: Health benefits and easy recipes

Swimming lessons save lives: What parents should know

Preventing and treating iliotibial (IT) band syndrome: Tips for pain-free movement

Wildfires: How to cope when smoke affects air quality and health

What can magnesium do for you and how much do you need?

Dry socket: Preventing and treating a painful condition that can occur after tooth extraction

What happens during sleep — and how to improve it

How is metastatic prostate cancer detected and treated in men over 70?

/

Health A to Z

The A to Z library is a collection of articles covering many of the most commonly searched medical conditions. Each article contains a description of the condition; the symptoms; how it is diagnosed, prevented, and treated; the prognosis; and when to seek professional advice.

Abdominal Adhesions

Abdominal Aortic Aneurysm

Absence Seizures (Petit Mal Seizures)

Achalasia

ACL (Anterior Cruciate Ligament) Injuries

Acne

Acoustic Neuroma

Acute Bronchitis

Acute Lymphocytic Leukemia (ALL) in Adults

Acute Lymphocytic Leukemia (ALL) in Children

Acute Myeloid Leukemia (AML)

Acute Pancreatitis

Acute Prostatitis

Acute Sinusitis

Adenocarcinoma of the lung

Adrenocortical Carcinoma

Age Spots (Solar Lentigo, Liver Spots)

Aging Overview

Alcohol Use Disorder (Alcoholism)

Alcohol Withdrawal

Allergy Overview

Allergy Shots (Allergen Immunotherapy)

Alopecia Areata

Altitude Sickness

Alzheimer's Disease

Amenorrhea

Amyloidosis

Amyotrophic Lateral Sclerosis (ALS)

Anal Cancer

Anal Disorders

Anal Itch (Pruritus Ani)

Anaphylaxis

Anemia Overview

Angina

Ankle Fracture

Ankle Sprain

Ankylosing Spondylitis

Anorexia Nervosa

Anterior Cruciate Ligament (ACL) Injuries

Antibiotic-Associated Diarrhea

Antiphospholipid Antibody Syndrome

Antisocial Personality Disorder

Aplastic Anemia

Appendicitis

Arm Fracture

Arthritis Associated With Inflammatory Bowel Disease

Asthma

Astigmatism

Asymptomatic Bacteriuria

Atherosclerosis

Athlete's Foot (Tinea Pedis)

Atrial Fibrillation

Attention Deficit Hyperactivity Disorder (ADHD)

Autism (Autism Spectrum Disorder)

Back Pain

Bacterial Vaginosis (Gardnerella Vaginitis)

Balanitis

Barium Enema

Barotrauma

Bartholin's Gland Cyst

Basal Cell Carcinoma

Bedsores (Decubitus Ulcers)

Bedwetting (Enuresis)

Behcet's Disease

Bells Palsy

Bile Duct Diseases

Biliary Colic

Bipolar Disorder (Manic Depressive Illness or Manic Depression)

Black Eye

Bladder Cancer

Bladder Infection (Cystitis)

Blepharitis

Blisters (Overview)

Body Lice

Boils and Carbuncles

Borderline Personality Disorder

Botulism

Bowel Obstruction

Bradycardia

Brain Abscess

Brain Tumor Overview

Breast Cancer

Broken Jaw

Broken Nose (Nasal Fracture)

Bulimia

Bunion

Bursitis

Campylobacteriosis

Cancer Overview

Candidiasis

Carbon Monoxide Poisoning

Carcinoid Tumors of the Lung

Cardiac Arrhythmias

Cardiomyopathy

Carpal Tunnel Syndrome

Cataracts

Celiac Disease (Non-Tropical Sprue)

Cellulitis

Cerebral Palsy

Cervical Cancer

Cervical Polyps

Cervicitis

Chemical Injury to the Eye

Chickenpox (Varicella)

Chlamydia

Cholecystitis

Chondromalacia

Chondrosarcoma

Chorionic Villus Sampling

Choroidal Melanoma

Chronic Fatigue Syndrome

Chronic Hepatitis

Chronic Laryngitis

Chronic Lymphocytic Leukemia (CLL)

Chronic Obstructive Pulmonary Disease (COPD)

Chronic Otitis Media, Cholesteatoma and Mastoiditis

Chronic Pancreatitis

Chronic Prostatitis

Chronic Sinusitis (in Adults)

Cirrhosis

Cluster Headache

Cogan's Syndrome

Collarbone (Clavicle) Fracture

Colon Polyps

Colorectal Cancer

Coma and Persistent Vegetative State

Common Cold (Viral Rhinitis)

Complex Regional Pain Syndrome (CRPS)

Concussion

Constipation and Impaction

Contact Dermatitis

Conversion Disorder (Functional Neurological Symptom Disorder)

Corneal Abrasion

Corns and Calluses

Coronary Artery Disease

Creutzfeldt-Jakob Disease (CJD)

Crohn's Disease

Crossed Eyes (Strabismus)

Croup

Curvature of the Penis (Peyronie's Disease)

Cystic Fibrosis

Cysts (Overview)

Cytomegalovirus (CMV)

Dandruff

Decompression Sickness

Delusional Disorder

Dementia

Depression Overview

Dermatofibroma

Detached Retina

Developmental Dysplasia of the Hip

Deviated Septum

Diabetes Mellitus Overview

Diabetic Ketoacidosis

Diabetic Nephropathy

Diabetic Neuropathies

Diarrhea

Dislocated Lens

Diverticulosis and Diverticulitis

Double Vision (Diplopia)

Down Syndrome

Drooping Eyelid (Ptosis)

Dry Eye Syndrome

Dry Skin

Dysfunctional Uterine Bleeding

Dyslexia

Dysthymia

Dysuria

Earache

Eczema

Emphysema

Encephalitis

Encopresis (Fecal Soiling)

End-Stage Renal Disease

Endocarditis

Endometriosis

Endophthalmitis

Enlarged Prostate (Benign Prostatic Hyperplasia)

Epidemic Pleurodynia

Epidermoid Cyst

Epididymitis And Orchitis

Epiglottitis

Epilepsy

Esophageal Cancer

Esophageal Rings And Webs

Esophageal Varices

Esophagitis

Essential Tremor

Ewing's Sarcoma

Extragonadal Germ Cell Tumors

Eye Socket Fracture (Fracture Of The Orbit)

Fallen Arch

Fallopian Tube Cancer

Familial Dysautonomia

Farsightedness (Hyperopia)

Febrile Seizures

Fecal Incontinence

Felon

Female Infertility

Fever

Fibroids

Fibromyalgia

Fifth Disease (Erythema Infectiosum)

Finger Dislocation

Flu (Influenza)

Food Allergy

Food Poisoning

Foot Sprain

Foot Ulcers

Foreign Body In Eye

Foreign Objects In The Ear

Fragile X Syndrome

Friction Blisters

Friedreich's Ataxia

Gallbladder and bile duct cancer

Gallstones

Gas (Flatulence)

Gastritis

Gastroenteritis In Adults

Gastroenteritis In Children

Gastroesophageal Reflux Disease (GERD)

Gastrointestinal Amebiasis

Gaucher Disease

Generalized Anxiety Disorder

Generalized Seizures (Grand Mal Seizures)

Genital Herpes

Genital Warts

Gestational Diabetes

Giant Cell Arteritis (Temporal Arteritis)

Giardiasis

Glaucoma

Glioblastoma Multiforme

Glomerulonephritis

Gonorrhea

Gout

Granulomatosis with polyangiitis

Graves' Disease

Graves' Eye Disease (Graves' Ophthalmopathy)

Guillain-Barre Syndrome

Hair Loss

Hammertoe

Hay Fever (Allergic Rhinitis)

Head and Neck Cancer

Head Injury In Adults

Head Injury In Children

Head Lice

Headache Overview

Hearing Loss in Adults

Hearing Loss in Children

Heart Attack (Myocardial Infarction)

Heart Failure

Heart Murmur

Heart Valve Problems

Heart Valve Replacement

Heat Stroke (Hyperthermia)

Heel Pain

Hematuria

Hemochromatosis

Hemophilia

Hemorrhagic Stroke

Hemorrhoids

Hepatitis A

Hepatitis B

Hepatitis C

Hepatitis Overview

Hereditary-Patterned Baldness

Hernia

Hernia Repair

Herniated Disk

Hiatal Hernia

High Blood Pressure (Hypertension)

High Cholesterol (Hypercholesterolemia)

Hip Fracture

Hirsutism

HIV/AIDS

Hives (Urticaria)

Hodgkin Lymphoma

Hot Flashes

Human Papillomavirus (HPV)

Huntington's Disease (Chorea)

Hydrocephalus

Hyperkeratosis

Hyperthyroidism

Hypoglycemia

Hypoparathyroidism

Hypothyroidism

Ichthyosis

Illness Anxiety Disorder

Immune Thrombocytopenic Purpura (ITP)

Impetigo

Impotence (Erectile Dysfunction)

Infectious Arthritis

Infectious Mononucleosis

Ingrown Toenail

Inguinal Hernia

Insomnia

Interstitial Cystitis

Intracranial Aneurysms

Iron Deficiency

Irritable Bowel Syndrome (IBS)

Jet Lag

Jock Itch (Tinea Cruris)

Juvenile Arthritis

Kaposi's Sarcoma

Kawasaki Disease

Keloids

Keratitis

Kidney Cancer

Kidney Failure

Kidney Stones

Knee Sprain

Lactose Intolerance

Lacunar Stroke

Langerhans' Cell Histiocytosis (Histiocytosis X)

Laryngitis

Latex Allergy

Lazy Eye (Amblyopia)

Lead Poisoning

Leg Edema

Leg Fracture

Leg Strain

Leukemia (Overview)

Liver Cancer

Long QT Syndrome

Lung Cancer Overview

Lupus (Systemic Lupus Erythematosus)

Lyme Disease

Lymphedema

Lymphoma Overview

Macular Degeneration

Major Depression

Malaria

Male Infertility

Malignant Hyperthermia

Marfan Syndrome

Maturity Onset Diabetes of the Young (MODY)

Measles (Rubeola)

Meckel's Diverticulum

Medication Allergy

Melanoma

Melasma (Chloasma)

Ménière's Disease

Meningitis

Menopause And Perimenopause

Mesothelioma

Metastatic Brain Tumors

Mid-Menstrual Cycle Pain (Mittelschmerz)

Middle-Ear Infection (Otitis Media)

Migraine

Miscarriage

Mitral Valve Prolapse

Molar Pregnancy

Moles (Nevi)

Molluscum Contagiosum

Morton's Neuroma

MRSA Skin Infection

Multiple Myeloma

Multiple Sclerosis

Mumps

Muscle Strain

Muscular Dystrophy

Myasthenia Gravis

Myelodysplastic Syndromes

Myocarditis

Myositis

Nabothian Cysts

Nail Trauma

Narcolepsy

Nasal Polyps

Nausea

Nearsightedness (Myopia)

Nephrectomy

Neuroblastoma

Neurofibromatosis

Non-Hodgkin Lymphoma

Non-Small Cell Lung Cancer

Nosebleed (Epistaxis)

Obesity

Obsessive-Compulsive Disorder (OCD)

Onycholysis

Optic Nerve Swelling (Papilledema)

Oral Cancer

Osgood-Schlatter Disease

Osteoarthritis

Osteoporosis

Osteosarcoma

Ovarian Cancer

Paget's Disease of Bone

Pain

Painful Sexual Intercourse (Dyspareunia)

Pancreatic Cancer

Pancreatitis Overview

Panic Disorders

Parathyroid Cancer

Parkinson's Disease

Paronychia

Partial Seizures (Focal Seizures)

Pelvic Inflammatory Disease (PID)

Peptic Ulcer

Perforated Eardrum

Pericarditis

Peripheral Arterial Disease

Peritonsillar Abscess

Pertussis (Whooping Cough)

Phenylketonuria (PKU)

Phimosis and Paraphimosis

Phobia

Pink eye (Conjunctivitis)

Pituitary Tumors

Pityriasis Rosea

Plague (Yersinia Pestis)

Plantar Fasciitis

Pleurisy And Pleural Effusion

Pneumoconiosis

Pneumonia

Pneumothorax

Polio

Polyarteritis Nodosa

Polychondritis

Polycystic Kidney Disease

Polycystic Ovary Syndrome

Polymyalgia Rheumatica

Post-Polio Syndrome

Post-Traumatic Stress Disorder

Posterior Cruciate Ligament (PCL) Injuries

Postpartum Depression

Prediabetes

Preeclampsia And Eclampsia

Premature Ejaculation

Premenstrual Syndrome (PMS)

Presbyopia

Priapism

Prostate Cancer

Pseudogout (CPPD)

Psoriasis

Psoriatic Arthritis

Pubic Lice Or Crab Lice

Pyelonephritis

Rash

Raynaud's Phenomenon

Reactive Arthritis

Rectocele

Respiratory Syncytial Virus

Restless Legs Syndrome

Retinal Vessel Occlusion

Retinitis Pigmentosa

Retinoblastoma

Retinopathy

Retrobulbar Neuritis

Retrograde Ejaculation

Reye Syndrome

Rhabdomyosarcoma

Rheumatoid Arthritis

Ringworm (Tinea)

Rocky Mountain Spotted Fever

Rosacea

Rotator Cuff Injury

Salivary Gland Disorders

Sarcoidosis

Scabies

Scarlet Fever

Schizophrenia

Schizotypal Personality Disorder

Sciatica

Scleritis

Scleroderma

Scoliosis

Screening for Birth Defects in Early Pregnancy (Combined Test, Integrated Test, and Quadruple Test)

Sebaceous Cysts

Seborrheic Dermatitis

Seborrheic Keratoses

Secondary Hypertension

Sedative, Hypnotic, or Anxiolytic Drug Use Disorder

Seizure Overview

Sexually Transmitted Diseases (Overview)

Shigellosis

Shin Splints

Shingles (Herpes Zoster)

Shoulder Dislocation

Shoulder Sprain

Sick Sinus Syndrome

Sickle Cell Anemia

Sjogren's Syndrome

Skin Tags (Acrochordon)

Sleep Apnea

Sleepwalking and Sleep Terrors

Small Cell Lung Cancer

Smallpox

Soft Tissue Sarcoma

Somatic Symptom Disorder

Sore Throat (Pharyngitis)

Spider Veins

Spina Bifida

Spinal Cord Trauma

Spinal Cord Tumors

Sprain (Overview)

Squamous Cell Carcinoma of the Lung

Squamous Cell Carcinoma of the Skin

Stomach Cancer

Stroke Overview

Stuttering

Styes And Chalazions

Subarachnoid Hemorrhage

Subdural Hematoma

Sun Allergy (Photosensitivity)

Sun-Damaged Skin

Superficial Thrombophlebitis

Swallowed Object

Swimmer's Ear (Otitis Externa)

Syphilis

Tachycardia

Takayasu's Arteritis

Tay-Sachs Disease

Tear Duct Infection (Dacryocystitis)

Telogen Effluvium

Tendonitis

Tennis Elbow (Lateral Epicondylitis)

Tension Headache

Testicular Cancer

Testicular Torsion

Tetanus

Throat Cancer (Larynx and Pharynx)

Thrombocytopenia

Thromboembolism (Deep Vein Thrombosis and Pulmonary Embolism)

Thrombotic Stroke

Thyroid Cancer

Tick Bites

Tics

Tinea Versicolor

Tinnitus

Toenail Fungus (Onychomycosis)

Torn Meniscus

Torsional Deformity

Tourette Syndrome

Toxic Shock Syndrome

Toxoplasmosis

Transient Ischemic Attack (TIA)

Traumatic Dislocation of the Hip

Traveler's Diarrhea

Trichomoniasis

Trigeminal Neuralgia (Tic Douloureux)

Tropical Sprue

Tuberculosis

Type 1 Diabetes Mellitus

Type 2 Diabetes Mellitus

Ulcerative Colitis

Undescended Testicle

Urethritis

Urinalysis

Urinary Health

Urinary Incontinence

Urinary Tract Infection in Men

Urinary Tract Infection in Women

Uterine And Bladder Prolapse

Uterine Cancer

Uveitis

Vaginal Atrophy (Atrophic Vaginitis)

Vaginal Cancer

Vaginal Discharge

Vaginal Yeast Infection

Vaginitis

Varicose Veins

Vascular Birthmarks

Vasculitis Overview

Vertigo

Vitamin B12 Deficiency

Vitiligo

Vocal Cord Disorders

Vulvar Cancer

Waldenström Macroglobulinemia

Warts

Wax Blockage Of The Ear Canal

Wilms' Tumor

Wrist Sprain

Yaws

Share

Print This Page

Disclaimer:

As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Please note the date of last review or update on all articles.

No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.

Recent Articles

Hemoglobin A1c (HbA1c): What to know if you have diabetes or prediabetes or are at risk for these conditions

What could be causing your blurry vision?

Avocado nutrition: Health benefits and easy recipes

Swimming lessons save lives: What parents should know

Preventing and treating iliotibial (IT) band syndrome: Tips for pain-free movement

Wildfires: How to cope when smoke affects air quality and health

What can magnesium do for you and how much do you need?

Dry socket: Preventing and treating a painful condition that can occur after tooth extraction

What happens during sleep — and how to improve it

How is metastatic prostate cancer detected and treated in men over 70?

/

Free Healthbeat Signup

Get the latest in health news delivered to your inbox!