S

Sacral dimple

Sacroiliitis

Salivary gland cancer

Salmonella infection

Sarcoidosis

Scabies

Scalp lichen planus

Scarlet fever

Schizoaffective disorder

Schizoid personality disorder

Schizophrenia

Schizotypal personality disorder

Schwannomatosis

Sciatica

Scleroderma

Scoliosis

Scorpion stings

Sebaceous gland carcinoma

Seborrheic dermatitis

Seborrheic keratosis

Secondary syphilis

Self injury or cutting

Semen allergy

Separated shoulder

Separation anxiety

Sepsis

Septic arthritis

Septicemic plague

Serotonin syndrome

Severe acute respiratory syndrome (SARS)

Sex headaches

Sexually transmitted diseases (STDs)

Shaken baby syndrome

Sheehan's syndrome

Shellfish allergy

Shigella infection

Shin splints

Shingles

Sick sinus syndrome

Sickle cell anemia

Sinus headaches

Sjogren's syndrome

Skin lichen planus

Sleep apnea

Sleep terrors (night terrors)

Sleepwalking

Small vessel disease

Smallpox

Social anxiety disorder (social phobia)

Soft tissue sarcoma

Solar urticaria

Solitary rectal ulcer syndrome

Soy allergy

Spermatocele

Spider bites

Spinal cord injury

Spinal headaches

Spinal stenosis

Spinal tumor

Spine tuberculosis

Sprained ankle

Sprains

Spring and summer seasonal affective disorder (summer depression)

Squamous cell carcinoma

Staphylococcal folliculitis

Staphylococcal scalded skin syndrome

Stevens Johnson syndrome

Stickler syndrome

Stomach cancer

Stomach polyps

Strains

Strep throat

Stress fractures

Stress incontinence

Stretch marks

Stroke

Stuttering

Stuttering priapism

Sty

Subconjunctival hemorrhage (broken blood vessel in eye)

Sudden (acute) pulmonary edema

Sudden cardiac arrest

Sudden infant death syndrome (SIDS)

Sun allergy

Sunburn

Superficial folliculitis

Swimmer's ear

Swimmer's itch

Swine flu (H1N1 flu)

Sycosis barbae

Syphilis

Syringomyelia