This list includes 40 Diseases that start with S, from “Sarcoidosis” to “Systemic Lupus Erythematosus”. It covers common infections, autoimmune conditions, genetic syndromes and chronic disorders, offering a practical A–Z reference for quick lookups.
Diseases that start with S are medical conditions whose names begin with the letter S and include infectious, autoimmune, genetic and chronic disorders. Historically, S-labelled diseases such as smallpox shaped public health, while others like Systemic Lupus Erythematosus remain important clinical challenges.
Below you’ll find the table with the columns ‘Disease’, ‘Symptoms’, ‘Causes’ and ‘Treatments’.
Disease: Standard name of the condition so you can identify it quickly and match it to other resources.
Symptoms: Brief list of the most common or notable signs so you can recognize typical presentations at a glance.
Causes: Primary cause and key risk factors summarized concisely so you understand likely origins and contributing mechanisms.
Treatments: Typical first-line therapies and referral notes so you know common management approaches and when to seek specialist care.
Diseases that start with S
| Name | Synonyms | Symptoms | Causes & Treatments |
|---|---|---|---|
| Sarcoidosis | Besnier-Boeck-Schaumann disease | Persistent dry cough; shortness of breath; fatigue; skin rashes | Cause: Unknown immune reaction; Treatment: Corticosteroids, immunosuppressants |
| Scabies | Sarcoptic mange, The seven-year itch | Intense itching (worse at night); pimple-like rash; burrows in skin | Cause: Sarcoptes scabiei mite; Treatment: Prescription creams or lotions |
| Scarlet Fever | Scarlatina | Red rash feeling like sandpaper; sore throat; high fever; strawberry tongue | Cause: Group A Streptococcus bacteria; Treatment: Antibiotics (penicillin) |
| Schistosomiasis | Bilharzia, Snail fever | Abdominal pain; diarrhea; blood in stool or urine; fever | Cause: Parasitic flatworms from contaminated fresh water; Treatment: Praziquantel medication |
| Schizophrenia | Hallucinations; delusions; disorganized thinking; social withdrawal | Cause: Genes and environment; Treatment: Antipsychotic medication, therapy | |
| Sciatica | Pain radiating from lower back down one leg; numbness; weakness | Cause: Herniated disk, bone spur on the spine; Treatment: Pain relievers, physical therapy | |
| Scleroderma | Systemic sclerosis, CREST syndrome | Hardened, tight patches of skin; cold, numb fingers/toes; joint pain | Cause: Autoimmune, overproduction of collagen; Treatment: No cure, symptom management |
| Scoliosis | Uneven shoulders or waist; one hip higher than the other; spine curvature | Cause: Often unknown (idiopathic); Treatment: Observation, bracing, surgery | |
| Scurvy | Fatigue; swollen, bleeding gums; joint pain; easy bruising | Cause: Severe vitamin C deficiency; Treatment: Vitamin C supplements, diet change | |
| Seasonal Affective Disorder | SAD, Winter depression | Depression symptoms during specific seasons; low energy; oversleeping | Cause: Reduced exposure to sunlight; Treatment: Light therapy, psychotherapy, antidepressants |
| Seborrheic Dermatitis | Cradle cap, Seborrheic eczema | Scaly patches; red skin; stubborn dandruff on scalp, face, or chest | Cause: Unknown, linked to yeast (fungus); Treatment: Medicated shampoos, creams |
| Sepsis | Septicemia, Blood poisoning | High heart rate; fever or low temperature; confusion; extreme pain | Cause: Body’s extreme response to an infection; Treatment: IV antibiotics, fluids, oxygen |
| Severe Acute Respiratory Syndrome (SARS) | High fever; dry cough; shortness of breath; muscle aches | Cause: SARS-associated coronavirus (SARS-CoV); Treatment: Supportive care (oxygen) | |
| Shigellosis | Shigella infection | Diarrhea (often bloody); fever; stomach cramps | Cause: Shigella bacteria; Treatment: Rest, fluids; severe cases need antibiotics |
| Shingles | Herpes zoster | Painful rash with blisters on one side of body; burning or tingling pain | Cause: Reactivation of chickenpox virus; Treatment: Antiviral drugs, pain relief |
| Sickle Cell Anemia | Sickle cell disease, Drepanocytosis | Episodes of severe pain (crises); fatigue; swelling of hands and feet; yellow skin | Cause: Genetic disorder; Treatment: Pain management, blood transfusions, medication |
| Silicosis | Shortness of breath; chronic cough; fatigue; chest pain | Cause: Inhaling crystalline silica dust; Treatment: No cure, supportive care (oxygen) | |
| Sinusitis | Rhinosinusitis, Sinus infection | Facial pain or pressure; stuffy or runny nose; headache; loss of smell | Cause: Viral or bacterial infection, inflammation; Treatment: Decongestants, nasal sprays |
| Sjögren’s Syndrome | Sicca syndrome | Dry eyes; dry mouth; fatigue; joint pain | Cause: Autoimmune disorder; Treatment: Artificial tears, saliva stimulants, medication |
| Sleep Apnea | Obstructive sleep apnea (OSA) | Loud snoring; stopping breathing during sleep; daytime sleepiness | Cause: Blockage of the airway during sleep; Treatment: CPAP machine, lifestyle changes |
| Smallpox | Variola | High fever; body aches; distinctive rash that becomes fluid-filled blisters | Cause: Variola virus; Treatment: No cure, vaccine prevents it |
| Social Anxiety Disorder | Social phobia | Intense fear of social situations; worry about embarrassment; avoiding people | Cause: Genes and environment; Treatment: Psychotherapy (CBT), medication (SSRIs) |
| Soft Tissue Sarcoma | A lump that may be painful; swelling; abdominal pain | Cause: Unknown, genetic mutations; Treatment: Surgery, radiation, chemotherapy | |
| Spina Bifida | Varies: opening in the back; leg weakness; bowel/bladder problems | Cause: Neural tube birth defect; Treatment: Surgery after birth, physical therapy | |
| Spinal Muscular Atrophy | SMA | Progressive muscle weakness; poor muscle tone; trouble with motor skills | Cause: Genetic disorder affecting motor neurons; Treatment: Disease-modifying therapies |
| Spinal Stenosis | Back or neck pain; numbness or weakness in limbs; balance problems | Cause: Age-related wear and tear, arthritis; Treatment: Physical therapy, medication, surgery | |
| Spondylolisthesis | Lower back pain; pain radiating down legs; muscle tightness | Cause: Vertebra slips out of place; genetics, overuse; Treatment: Physical therapy, rest, surgery | |
| Staphylococcal Infection | Staph infection, MRSA | Boils or pus-filled bumps on skin; redness; swelling; pain | Cause: Staphylococcus bacteria; Treatment: Antibiotics, drainage of abscesses |
| Stevens-Johnson Syndrome | SJS | Flu-like symptoms followed by a painful red/purple rash that blisters | Cause: Often a severe reaction to medication; Treatment: Hospitalization, stopping causal drug |
| Stiff Person Syndrome | SPS | Progressive muscle stiffness; painful muscle spasms | Cause: Autoimmune disorder; Treatment: Muscle relaxants, immunotherapy |
| Stomach Cancer | Gastric cancer | Indigestion; stomach pain; feeling full after small meals; unintentional weight loss | Cause: H. pylori infection, smoking, diet; Treatment: Surgery, chemotherapy, radiation |
| Strabismus | Crossed eyes, Wall eyes | Eyes don’t look in the same direction at the same time; poor depth perception | Cause: Nerve or muscle problem in the eye; Treatment: Glasses, eye patch, surgery |
| Strep Throat | Streptococcal pharyngitis | Severe sore throat; pain when swallowing; fever; tiny red spots on roof of mouth | Cause: Group A Streptococcus bacteria; Treatment: Antibiotics (penicillin) |
| Stroke | Cerebrovascular accident (CVA) | Sudden numbness or weakness (one side); confusion; trouble speaking or seeing | Cause: Blocked or burst blood vessel in brain; Treatment: Emergency clot-busting drugs |
| Stye | Hordeolum | Painful red lump on the edge of the eyelid; swelling of the eyelid | Cause: Bacterial infection in an oil gland; Treatment: Warm compresses, antibiotics |
| Subarachnoid Hemorrhage | Sudden, severe “thunderclap” headache; nausea; loss of consciousness | Cause: Ruptured brain aneurysm, head injury; Treatment: Emergency surgery or procedure | |
| Sudden Infant Death Syndrome | SIDS, Crib death | None; unexpected death of a seemingly healthy infant under 1 year old | Cause: Unknown, likely multiple factors; Treatment: Prevention (safe sleep practices) |
| Syphilis | Painless sore (chancre); followed by a body rash; can be asymptomatic | Cause: Treponema pallidum bacteria (STI); Treatment: Antibiotics (penicillin) | |
| Syringomyelia | Progressive weakness and pain in back, shoulders, arms, or legs; headaches | Cause: Cerebrospinal fluid-filled cyst (syrinx) in spinal cord; Treatment: Monitoring, surgery | |
| Systemic Lupus Erythematosus | SLE, Lupus | Fatigue; joint pain; butterfly-shaped facial rash; fever | Cause: Autoimmune disorder; Treatment: Anti-inflammatory drugs, immunosuppressants |
Descriptions
Sarcoidosis
An inflammatory disease where tiny cell clumps (granulomas) form in organs, most often the lungs. It may resolve on its own, but see a doctor for persistent cough or breathing issues.
Scabies
A contagious skin infestation caused by a tiny mite that burrows into the skin to lay eggs. It spreads through close physical contact. See a doctor for diagnosis and effective treatment.
Scarlet Fever
A bacterial illness, mainly in children, causing a distinct pink-red rash. It’s a complication of strep throat and needs prompt antibiotic treatment. See a doctor if suspected.
Schistosomiasis
A disease caused by parasitic worms in certain tropical and subtropical countries. Infection occurs through skin contact with contaminated water. See a doctor if you’ve traveled to an at-risk area.
Schizophrenia
A serious chronic mental disorder affecting how a person thinks, feels, and behaves. It requires lifelong treatment to manage symptoms. Seek medical help for any psychotic symptoms.
Sciatica
Pain that travels along the path of the sciatic nerve, which branches from your lower back through your hips and down each leg. It usually affects only one side. See a doctor for persistent pain.
Scleroderma
A rare autoimmune disease that involves the hardening and tightening of the skin and connective tissues. It can affect internal organs. Consult a rheumatologist for diagnosis.
Scoliosis
A sideways curvature of the spine that most often occurs during the growth spurt just before puberty. Most cases are mild, but some may require treatment. See a doctor for spinal screening.
Scurvy
A disease resulting from a lack of vitamin C, which is needed for making collagen. It’s rare in developed countries but treatable with vitamin C. Consult a doctor for diagnosis.
Seasonal Affective Disorder
A type of depression that’s related to changes in seasons. Symptoms typically start in the fall and continue into the winter months. See a doctor if you feel down for days at a time.
Seborrheic Dermatitis
A common skin condition that mainly affects your scalp, causing scaly patches and red skin. In infants, it’s known as cradle cap. It is a long-term condition that can be managed.
Sepsis
A life-threatening medical emergency caused by the body’s overwhelming response to an infection, which can lead to tissue damage and organ failure. Sepsis requires immediate emergency medical care.
Severe Acute Respiratory Syndrome (SARS)
A contagious and sometimes fatal respiratory illness. An outbreak in 2003 was contained, and there have been no known cases since 2004. It caused a global health alert due to its severity.
Shigellosis
An infectious disease caused by a group of bacteria called Shigella. It is very contagious and spreads through contaminated food or water. Good handwashing is key to prevention.
Shingles
A viral infection that causes a painful rash, caused by the same virus as chickenpox. A vaccine is available for older adults. See a doctor promptly if you suspect shingles to reduce complication risks.
Sickle Cell Anemia
An inherited red blood cell disorder where cells are shaped like sickles, causing blockages and pain. It’s a lifelong condition that requires specialized medical care.
Silicosis
A long-term lung disease caused by inhaling large amounts of crystalline silica dust, usually over many years in workplace settings. It is incurable but preventable with safety measures.
Sinusitis
Inflammation of the tissue lining the sinuses, often following a cold. Most cases are viral and resolve on their own, but see a doctor if symptoms are severe or persist for over 10 days.
Sjögren’s Syndrome
An autoimmune disorder where the immune system attacks glands that make moisture, such as tears and saliva. It’s a chronic condition that can also affect joints, skin, and organs.
Sleep Apnea
A common sleep disorder in which breathing repeatedly stops and starts. It can lead to serious health problems. See a doctor if you have symptoms, as treatment is very effective.
Smallpox
A contagious and deadly disease that was officially eradicated worldwide in 1980 through vaccination. The virus no longer exists in nature.
Social Anxiety Disorder
A chronic mental health condition with an intense, persistent fear of being judged by others. It can disrupt daily life but is highly treatable with therapy and/or medication.
Soft Tissue Sarcoma
A rare type of cancer that begins in the tissues that connect, support, and surround other body structures, such as muscle, fat, and blood vessels. See a doctor for any new or growing lump.
Spina Bifida
A birth defect where there is incomplete closing of the backbone and membranes around the spinal cord. Taking folic acid before and during pregnancy greatly reduces the risk.
Spinal Muscular Atrophy
A group of genetic diseases that cause progressive muscle weakness and atrophy. New treatments have significantly improved the outlook, making early diagnosis and care crucial.
Spinal Stenosis
A narrowing of the spaces within your spine, which can put pressure on the nerves. It most often occurs in the lower back and neck. See a doctor for persistent pain or weakness.
Spondylolisthesis
A spinal condition where one of the lower vertebrae slips forward onto the bone directly beneath it. It often causes lower back pain. See a doctor for diagnosis and a management plan.
Staphylococcal Infection
An infection caused by staph bacteria, commonly found on skin. It can range from minor skin issues to life-threatening infections. Good hygiene helps. See a doctor for skin infections.
Stevens-Johnson Syndrome
A rare, serious disorder of the skin and mucous membranes. It’s a medical emergency that is often triggered by a medication. Seek immediate emergency care for a rapidly spreading, painful rash.
Stiff Person Syndrome
A rare neurological disorder with features of an autoimmune disease. It causes muscle stiffness in the torso and limbs and a heightened sensitivity to stimuli. Consult a neurologist.
Stomach Cancer
Cancer that begins in the cells lining the stomach. It often has no early symptoms. Risk factors include chronic H. pylori infection. See a doctor for persistent digestive problems.
Strabismus
A condition in which the eyes do not properly align with each other when looking at an object. It is common in children and requires early treatment to prevent vision loss.
Strep Throat
A bacterial infection in the throat and tonsils that is common in children. It requires antibiotics to prevent complications like rheumatic fever. See a doctor for a severe sore throat.
Stroke
A medical emergency where blood supply to the brain is interrupted. Fast treatment is critical to reduce brain damage and long-term disability. Call emergency services immediately for symptoms.
Stye
A red, painful lump near the edge of your eyelid that may look like a boil or a pimple. Most styes are harmless and resolve on their own, but see a doctor if it doesn’t improve.
Subarachnoid Hemorrhage
Bleeding in the space between the brain and the tissue covering the brain. It is a medical emergency that requires immediate treatment to prevent brain damage. Call 911 for a thunderclap headache.
Sudden Infant Death Syndrome
The unexplained death, usually during sleep, of a healthy baby less than a year old. The cause is unknown, but safe sleep practices can greatly reduce the risk.
Syphilis
A sexually transmitted infection (STI) that can cause serious health problems if left untreated. It progresses in stages and is curable with antibiotics. Regular STI screening is important.
Syringomyelia
A rare disorder where a fluid-filled cyst forms within the spinal cord. This cyst, called a syrinx, can expand over time, damaging the spinal cord. Consult a neurologist.
Systemic Lupus Erythematosus
A chronic autoimmune disease where the body’s immune system attacks its own tissues and organs. Management focuses on controlling symptoms and preventing flares. Consult a rheumatologist.