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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.
R
-
Radiofrequency ablation
see ablation, radiofrequency -
Radiolabelling
where a radioactive tag is attached to a substance -
Radiotherapy
treatment with radiation -
Raynaud's disease (phenomenon, syndrome)
severe narrowing of blood vessels in the cold <with skin turning white or blue> -
Receptor
target -
Rectum
the lowest part of the gut <that stores faeces> -
Recurrence
when <symptoms/the disease> come(s) back <after treatment> -
Recurrent
<has come back/keeps coming back> <after previous treatment> -
Refractory
when treatment does not work -
Registry (patient or disease)
ongoing collection of information about <a specific group of> patients affected by a particular condition -
Relapse
when <symptoms/the disease> come(s) back <after treatment> -
Relapse-free survival
[used in cancer trials] how long patients live without their disease coming back -
Relapsing-remitting multiple sclerosis
see multiple sclerosis, relapsing-remitting -
Remission
a period without disease symptoms after treatment -
Renal
kidney -
Renal failure
inability of the kidneys to work properly -
Renal failure, chronic
long-term, progressive decrease in the kidneys’ ability to work properly -
Renal impairment
reduced kidney function -
Resistant (treatment)
when treatment does not work -
Respiratory depression
when breathing is too slow and shallow -
Respiratory failure
inability of the lungs <to work properly><to take in oxygen and get rid of carbon dioxide properly> -
Respiratory insufficiency
difficulty breathing -
Respiratory system
lungs and airways -
Respiratory tract congestion
blocked airways -
Respiratory tract infection
Infection of the airways -
Response
improvement related to treatment -
Response rate
[used in cancer trials] percentage of patients who improve <on treatment> -
Restless legs syndrome
a disorder where the patient has uncontrollable urges to move the legs to stop uncomfortable, painful or odd sensations, usually at night -
Reticulocytopenia
low levels of reticulocytes, a type of immature red blood cell -
Retina
the light-sensitive membrane at the back of the eye -
Retinopathy
damage to the retina -
Revascularisation
restoration of blood flow -
Reverse transcriptase
an enzyme produced by <virus> that allows it to infect cells in the body and make more viruses -
Rhabdomyolysis
breakdown of muscles often leading to kidney damage -
Rheumatoid arthritis
a disease with painful swelling and damage of joints <caused by the immune system mistakenly attacking healthy cells> -
Rhinitis
stuffy and runny nose -
Rhinitis, allergic
stuffy and runny nose <with inflammation> caused by an allergy <e.g., hay fever or dust-mite allergy> -
Rhinorrhoea
runny nose -
Ribosomes
the parts of the cell that produce proteins -
Rigors
shaking chills -
RNA
genetic material <instructions for producing proteins> -
Rotavirus
a virus that causes gastroenteritis -
Rubella
German measles