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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.
S
-
Saccadic (eye movements)
rapid eye movements -
Scleroderma
hardening of the skin and connective tissue around internal organs -
Sclerosis, systemic
see scleroderma -
Seasonal allergic conjunctivitis
inflammation of the eyes caused by pollen in patients with hay fever -
Seasonal allergic rhinitis
hay fever -
Secondary progressive multiple sclerosis
see multiple sclerosis, secondary progressive -
Sedation
<calming effect> <induce sleepiness> -
Seizure
use seizure; do not use fit -
Seizure, absence
a type of seizure during which a person has a blank stare but is partly aware of surroundings -
Seizure, atonic
brief loss of muscle control and reduced consciousness -
Seizure, atypical absence
a type of seizure during which a person has a blank stare <possibly losing awareness of surroundings> -
Seizure, generalised
seizure affecting most or all of the brain -
Seizure, myoclonic
short, shock-like jerks of a muscle or group of muscles -
Seizure, partial<-onset> <with <or without> secondary generalisation>
epileptic seizure starting in one specific part of the brain. <Secondary generalisation is when the seizure subsequently spreads to the whole brain> -
Seizure, tonic
brief seizure with muscle contraction -
Seizure, tonic-atonic
a type of seizure that often involves the patient falling to the floor -
Seizure, tonic-clonic
major seizure, including loss of consciousness -
Sensitivity (of disease)
when a condition is treatable by a <medicine> <group of medicines> -
Sensitivity (test)
a measure of how well a test can detect those who have a <disease> <condition> -
Sensory neuropathy
see neuropathy, sensory -
Sepsis
<when bacteria and their toxins circulate in the blood leading to organ damage><blood poisoning> -
Septic shock
a dangerous drop in blood pressure caused by severe infection -
Septicaemia
blood poisoning -
Seroconversion
development of antibodies <(proteins in the body’s defence system)> against a specific target -
Serum sickness
allergic reaction to injected proteins <and blood products> <with fever, rash, joint pain, digestive system problems and headache> -
Shingles
a painful, blistering rash in one part of the body -
Shock
a steep fall in blood pressure -
Sinus node
the 'pacemaker' for the heart that controls the heart contractions and regulates heart rate -
Sinus rhythm
normal heartbeat -
Sinuses
air-filled passageways in the bones around the nose and eyes -
Sinusitis
inflammation of the sinuses -
Sleep apnoea
see apnoea, sleep -
Sleep latency
the length of time taken to fall asleep -
Slit lamp
an instrument used by eye specialists to look into the eye -
Soft tissues
tissues just below the skin -
Somnolence
sleepiness -
Spasticity
continuously stiffened muscles -
Specificity (test)
a measure of how well a test can distinguish people with a condition from those who don’t have it -
Splenomegaly
enlarged spleen -
Sputum
phlegm -
ST segment elevation
an abnormal reading on the electrocardiogram (ECG) -
Stable angina pectoris
see angina pectoris -
Standard of care
treatment that medical experts consider most appropriate -
Statin
the standard type of medicine used to reduce cholesterol -
Status epilepticus
an epileptic seizure, or series of seizures, lasting longer than 5 minutes -
Stem cell transplant
see haematopoietic (blood) stem cell transplantation -
Stem cells (haematopoietic stem cells)
cells that can develop into different types of (blood) cells -
Stenosis
narrowing of a <body passage> <blood vessel> -
Stenosis, aortic
narrowing of the aorta -
Stent
a short tube placed in an artery to prevent it closing up -
Steroid
use corticosteroid -
Stevens-Johnson syndrome
life-threatening reaction with flu-like symptoms and painful rash affecting the skin, mouth, eyes and genitals -
Stomatitis
inflammation of the lining of the mouth -
Stress incontinence
see incontinence, stress -
Stroke
sudden interruption of blood flow in the brain which can cause paralysis and unconsciousness -
Stroke, haemorrhagic
stroke <(sudden interruption of blood flow in the brain)> caused by bleeding in a part of the brain -
Stroke, ischaemic
stroke <(sudden interruption of blood flow in the brain)> caused by blocked blood supply to a part of the brain -
Subcutaneous injection
injection under the skin -
Subcutaneous(ly)
under the skin -
Sublingual tablet
a tablet that is placed under the tongue where it dissolves -
Supportive care
treatment to prevent or relieve the symptoms of the disease <but not specific treatment against the disease> -
Surfactant (lung)
a substance lining the airsacs which allows gases to pass easily between the lung and blood -
Survival rate, overall
[used in cancer trials] percentage of patients who live for a specific period <after diagnosis or treatment> -
Survival, overall
[used in cancer trials] how long patients live -
Suspension
a liquid with solid particles in it -
Sutured
stitched -
Syncope
fainting -
Systemic (side effects)
side effects that can affect anywhere in the body -
Systemic lupus erythematosus
a condition in which the body’s defence system attacks normal tissue causing symptoms such as swollen joints, tiredness and rashes -
Systemic treatment
treatment with <a> medicine<s> given <by mouth> <or> <by injection> -
Systolic blood pressure
see blood pressure, systolic