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This resource focuses on side effects and other terms used in medicines information and assessments of medicines. It does not include terms that are used only rarely, nor does it cover most disease states or technical terms.
How to use EMA’s medical terms simplifier
- You can search for a term or click on a letter below to see terms beginning with that letter.
- Each entry contains a short description. For some, a longer or alternative description is available by selecting the term.
- We use ‘< >’ to indicate alternative or optional wording.
EMA’s medical terms simplifier will be updated periodically. For comments or suggestions, you can use our Medical terms simplifier comments form.
T
-
T cells
cells in the immune system -
T lymphocytes
see T cells -
Tachycardia
rapid heartbeat -
Tachypnoea
rapid breathing -
Tapering (dose)
reducing the dose gradually -
Tardive dyskinesia
uncontrolled movements of the face and jaw -
Tenosynovitis
inflammation of the sheath surrounding a tendon -
Teratogen
a substance that can cause birth defects in the unborn baby -
Teratogenicity
ability to cause birth defects -
Thrombin
a protein involved in blood clotting -
Thrombocytopenia
low levels of blood platelets <which can lead to bleeding and bruising> -
Thrombocytopenic purpura
formation of blood clots in small blood vessels, lowering the level of platelets and causing purple spots on the skin -
Thromboembolism
problems due to the formation of blood clots in the blood vessels -
Thrombolytic
dissolves blood clots -
Thrombophlebitis
inflammation in a vein leading to a blood clot <and blockage> -
Thrombosis
formation of blood clots in the blood vessels -
Thrombotic events
problems due to the formation of blood clots in the blood vessels -
Thymus gland
a gland <in the chest> that prepares <cells> <lymphocytes> to help the body’s defences -
Tibia
shin bone -
Time to (disease) progression
[used in cancer trials] the time until the disease started worsening <again> -
Time to treatment failure
[used in cancer trials] the time until the treatment stopped working -
Tinnitus
ringing or buzzing in the ears -
Tonic seizure
see seizure, tonic -
Tonic-atonic seizure
see seizure, tonic-atonic -
Tonic-clonic seizure
see seizure, tonic-clonic -
Tonsillitis
infection of the tonsils -
Tophi
deposits of uric acid crystals in joints, skin or cartilage <which can cause damage> -
Topically
on the skin -
Torsades de pointes
abnormal electrical activity in the heart with life-threatening rhythm disturbance -
Torticollis
see cervical dystonia -
Toxic epidermal necrolysis
life-threatening reaction with flu-like effects and blistering in the skin, mouth, eyes and genitals -
Toxin
a harmful substance produced by infectious organisms -
Toxoid
an inactivated toxin -
Trachea
windpipe -
Transdermal patch
patch to give <a medicine> <medicines> through the skin -
Transplant rejection
when the immune system attacks the transplanted organ -
Trauma
<severe> injury -
Treatment-experienced
<had been> treated for <disease> before -
Treatment-naïve
<had> never <been> treated for <disease> -
Tremor
shaking -
Triglycerides
a type of fat -
Trismus
contraction of the jaw muscles that hold the mouth shut -
Tumour flare reaction
a side effect that is similar to worsening of the cancer<, symptoms may include painful and swollen lymph nodes, enlarged spleen, slight fever, bone pain and skin rash> -
Tumour lysis syndrome
a serious <side effect> <complication> with rapid break down of cancer cells <causing high levels of uric acid, potassium and phosphate>