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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.
N
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Naevus/nevus
<mole> <visible area of skin damage> -
Naïve patients
patients who have not been treated before -
Nanobody
a small antibody -
Narcolepsy
a sleep disorder that causes a person to fall asleep suddenly and unexpectedly -
Narrow-angle glaucoma
see glaucoma, angle-closure -
Nasal congestion
a blocked nose -
Nasal polyps
growths in the lining of the nose -
Nasogastric tube
a tube through the nose to the stomach -
Nasopharyngitis
inflammation of the nose and throat -
Nausea
feeling sick -
Nebuliser
device to produce a mist <of the medicine> for the patient to breathe in <through a mask or mouthpiece> -
Necrosis
death of cells or tissue -
Neoadjuvant treatment
preliminary treatment to shrink the <cancer> <tumour> -
Neonate
newborn baby -
Neonatologist
doctor specialising in treating newborn babies -
Neoplasm
cancerous or non-cancerous growths -
Nephritis
kidney inflammation -
Nephrolithiasis
kidney stones -
Nerve block
procedure to block sensation to a part of the body -
Neuralgia
nerve pain -
Neuralgia, post-herpetic
long-lasting nerve burning pain that may occur after shingles -
Neuroleptic malignant syndrome
a dangerous reaction with fever, rigid muscles, changing blood pressure and coma, usually caused by antipsychotic medicines -
Neurological
relating to the brain or nerves -
Neuropathic pain
see pain, neuropathic -
Neuropathic ulcer
see ulcer, neuropathic -
Neuropathy
nerve damage -
Neuropathy, peripheral
nerve damage in arms and legs <causing pain or numbness, burning and tingling> -
Neuropathy, peripheral motor
nerve damage causing difficulty with movement -
Neuropathy, sensory
nerve damage affecting sensation of pain, temperature and touch -
Neuropsychiatric disorders
disorders of the brain and nerves resulting in altered thinking or behaviour -
Neurosurgery
surgery on the nervous system, including the brain -
Neurotransmitter
a substance that nerve cells use to communicate with neighbouring cells
-
Neutropenia
low levels of neutrophils, a type of white blood cell <that fights infection> -
Neutropenia, febrile
low levels of white blood cells with fever <due to infection> -
Neutropenic
with low levels of neutrophils, a type of white blood cell -
Neutropenic fever
see neutropenia, febrile -
Neutrophil
a type of white blood cell <that fights infection> -
Nocturia
need to pass urine at night -
Non-Hodgkin's lymphoma
see lymphoma -
Nonclinical studies
laboratory studies -
Nosocomial
<infection> <disease> picked up in hospital