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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.
L
-
Lacerations
cuts -
Lacrimation
watery eyes -
Lactate dehydrogenase
a marker for tissue damage -
Lactic acidosis
a build-up of lactic acid in the body -
Larynx
voice box -
Laxatives
medicines that treat constipation -
Lean body mass
body weight excluding fat -
Lesion
injury; abnormality -
Lethargy
lack of energy -
Leucocytes
white blood cells -
Leucocytosis
high levels of white blood cells -
Leucopenia
low levels of white blood cells -
Leukaemia
cancer of the white blood cells -
Limb
arm or leg -
Lipids
fats -
Lipoatrophy
loss of fat below the skin <that can change body shape> -
Lipodystrophy (syndrome)
changes in the distribution of body fat -
Liver disease, compensated
when the liver is damaged but is still able to work <adequately> -
Liver disease, decompensated
when the liver is damaged and can no longer work adequately -
Liver impairment
problems with the liver -
Local anaesthetic
see anaesthetic, local -
Long QT syndrome
see QT<c> prolongation -
Low density lipoprotein (LDL)-cholesterol
‘bad’ cholesterol -
Lower respiratory tract infection
infection of the lungs such as bronchitis or pneumonia -
Lumbar puncture
inserting a needle into the lower spine <to test for> <to treat> conditions affecting the spinal cord and brain> -
Lumbar vertebra
one of the bones in the lower part of the spine -
Lung disease, interstitial
disorders causing scarring in the lungs -
Luteinising hormone (LH)
the hormone that triggers the release of eggs during the menstrual cycle -
Lymphadenopathy
enlarged lymph nodes, or 'swollen glands' -
Lymphatic system
a network of vessels that transport fluid from tissues through the lymph nodes and into the bloodstream -
Lymphocele
collection of lymph fluid usually in the lower belly -
Lymphocytes
a type of white blood cell -
Lymphoma
cancer of lymphocytes, white blood cells involved in the body’s defences -
Lymphopenia
low levels of lymphocytes, a type of white blood cell -
Lyophilisate
medicine <or food> that has been dried <by freeze drying> -
Lysis
cell death