- TAA see Aortic Aneurysm
- Tachycardia see Arrhythmia
- Tachypnea see Breathing Problems
- Tailbone Disorders
- Talk to Your Doctor see Talking With Your Doctor
- Talking With Your Doctor
- Tanning
- Tardive Dyskinesia see Movement Disorders
- Taste and Smell Disorders
- Tattoos see Piercing and Tattoos
- Tay-Sachs Disease
- TB see Tuberculosis
- TBI see Traumatic Brain Injury
- Tears
- Teas, Herbal see Herbal Medicine
- Teas, Medicinal see Herbal Medicine
- Teen Depression
- Teen Development
- Teen Drug Abuse see Drugs and Young People
- Teen Health
- Teen Mental Health
- Teen Nutrition see Child Nutrition
- Teen Sexual Health
- Teen Smoking see Smoking and Youth
- Teen Violence
- Teenage Drinking see Underage Drinking
- Teenage Pregnancy
- Teens and Diabetes see Diabetes in Children and Teens
- Teeth see Tooth Disorders
- Telehealth
- Temperature see Vital Signs
- Temporal Arteritis see Giant Cell Arteritis
- Temporomandibular Disorders
- Temporomandibular Joint Dysfunction see Temporomandibular Disorders
- Tendinitis
- Tennis Elbow see Elbow Injuries and Disorders
- Tension Headache see Headache
- Terminal Care see End of Life Issues
- Terrorist Attacks see Biodefense and Bioterrorism
- Testicular Cancer
- Testicular Disorders
- Tetanus
- Tetanus, Diphtheria, and Pertussis Vaccines
- Thalassemia
- Thiamine see B Vitamins
- Thirst see Dehydration
- Thoracentesis see Pleural Disorders
- Thoracic Aortic Aneurysm see Aortic Aneurysm
- Thoracic Injuries see Chest Injuries and Disorders
- Thoracic Outlet Syndrome
- Three Day Measles see Rubella
- Throat Cancer
- Throat Disorders
- Thrombocytopenia see Platelet Disorders
- Thrombophlebitis see Blood Clots
- Thrush see Yeast Infections
- Thumb Injuries see Finger Injuries and Disorders
- Thymus Cancer
- Thyroid Cancer
- Thyroid Diseases
- Thyroid Tests
- Thyrotoxicosis see Hyperthyroidism
- TIA see Transient Ischemic Attack
- Tic Douleureux see Trigeminal Neuralgia
- Tick Bites
- Tickborne Diseases see Tick Bites
- Tinea Infections
- Tinea Pedis see Athlete's Foot
- Tinnitus
- Tiredness see Fatigue
- Tissue Donation see Organ Donation
- TMD see Temporomandibular Disorders
- TMJ see Temporomandibular Disorders
- Tobacco Smoking see Smoking
- Tobacco, Smokeless see Smokeless Tobacco
- Toddler Development
- Toddler Health
- Toddler Nutrition
- Toe Injuries and Disorders
- Toenails see Nail Diseases
- Tongue Cancer see Oral Cancer
- Tongue Disorders
- Tonsillectomy see Tonsillitis
- Tonsillitis
- Tonsils see Tonsillitis
- Tooth Decay
- Tooth Disorders
- Tornadoes
- Torticollis see Dystonia
- Tourette Syndrome
- Toxemia see High Blood Pressure in Pregnancy
- Toxic Shock Syndrome see Sepsis
- Toxoplasmosis
- TPN see Nutritional Support
- Trace Elements see Dietary Supplements
- Tracheal Disorders
- Tracheostomy see Critical Care; Tracheal Disorders
- Traffic Accidents see Motor Vehicle Safety
- Trans Fats see Dietary Fats
- Transfusion see Blood Transfusion and Donation
- Transgender Health see LGBTQIA+ Health
- Transient Ischemic Attack
- Transplantation see Organ Transplantation
- Traumatic Brain Injury
- Traveler's Health
- Treacher-Collins Syndrome see Craniofacial Abnormalities
- Tremor
- Tribal Health see American Indian and Alaska Native Health
- Trichomoniasis
- Trigeminal Neuralgia
- Triglycerides
- Triplets see Twins, Triplets, Multiple Births
- Trisomy 21 see Down Syndrome
- Tropical Medicine see Traveler's Health
- TSC see Tuberous Sclerosis
- Tsunamis
- Tubal Ligation
- Tubal Pregnancy see Ectopic Pregnancy
- Tuberculosis
- Tuberous Sclerosis
- Tularemia see Tick Bites
- Tumor see Cancer
- Tumors and Pregnancy
- Tumors, Benign see Benign Tumors
- Turner Syndrome
- Twins, Triplets, Multiple Births
- Type 1 Diabetes see Diabetes Type 1
- Type II Diabetes see Diabetes Type 2
- Typhoid Fever see Salmonella Infections