- Thalidomide
- Thalitone
- thallium (201Tl) chloride
- Thalomid
- Tham brand of tromethamine
- Thatzit
- The Magic Bullet
- Thebacon
- Thenalidine
- Thenalidine, Combinations
- Theo G
- Theo-24
- Theo-Dur Sprinkles
- Theo-Time
- Theo-X
- Theobid
- Theobromine
- Theobromine, Combinations
- TheoCap
- Theochron
- Theoclear-80
- Theocon
- Theocon Elixir
- Theodrenaline
- Theodur
- Theolair
- Theolate
- Theomar G.G.
- Theophyll-GG
- Theophylline
- Theophylline And Adrenergics
- Theophylline, Combinations Excl. Psycholeptics
- Theophylline, Combinations With Psycholeptics
- Theosol-80
- Theovent
- Thera-D
- Thera-Flur-N
- Thera-Sal
- TheraBreath
- Theracort Anti-Itch
- Theraflu Cold & Cough
- Theraflu Cold & Sore Throat
- Theraflu Cold & Sore Throat
- Theraflu Daytime Severe Cold
- Theraflu Daytime Severe Cold & Cough
- Theraflu Flu & Chest Congestion
- Theraflu Flu & Sore Throat
- Theraflu Flu & Sore Throat
- Theraflu Flu and Cold Medicine Powder
- Theraflu Max-D
- Theraflu Multi Symptom
- Theraflu Nightime Maximum Strength
- Theraflu Nighttime Severe Cold
- Theraflu Nighttime Severe Cold Capsule
- Theraflu No Drowsiness Maximum Strength
- Theraflu Severe Cold & Cough Nighttime
- Theraflu Severe Cold Nighttime
- Theraflu Sinus
- Theraflu Sore Throat Maximum Strength
- Theraflu Warming Cold & Chest Congestion
- Theraflu Warming Relief
- Theraflu, Flu, Cold, and Cough
- Theramycin
- Theraplex Z
- TheraSeal Hand Protection
- TheraTears Nutrition
- Therevac Plus
- Thermazene
- Thermotabs
- Thiamazole, Combinations
- Thiamine
- Thiamphenicol
- Thiamphenicol, Combinations
- Thiazinam
- Thiethylperazine
- Thioacetazone And Isoniazid
- Thiocolchicoside
- Thioctic Acid
- Thioguanine
- Thiola
- Thiomersal
- Thiopental
- Thioplex
- Thiopropazate
- Thioproperazine
- Thioridazine
- Thiosulfate
- Thiosulfil Forte
- Thiotepa
- Thiothixene
- Thiotixene
- Thiram
- Thomapyrin
- Thonzylamine
- Thorazine
- Thrive
- Throat-Releev
- Thrombate III
- Thrombin
- Thrombin-JMI
- Thrombocytes
- Thrombogen
- Thybine
- Thymopentin
- Thyrel TRH
- Thyroid Gland Preparations
- ThyroSafe
- ThyroShield
- Thyrotropin