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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.
G
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Gangrene
decay and death of tissue -
Gastric retention
when the stomach does not empty properly -
Gastritis
inflammation of the stomach lining -
Gastro-oesophageal reflux disease
disease where stomach acid rises up into the oesophagus -
Gastro-resistant
<tablets> <capsules> that can pass through the stomach intact -
Gastroenteritis
diarrhoea and vomiting -
Gastrointestinal
stomach and gut -
Gastrostomy
inserting a tube through the skin into the stomach; see PEG -
General anaesthetic
see anaesthetic, general -
Generalised anxiety disorder
long-term anxiety or nervousness about everyday matters -
Generalised seizure
see seizure, generalised -
Genotoxic substance
a substance that is harmful to DNA, the genetic material in cells -
Glaucoma
damage to the nerve in the eye <usually caused by high pressure in the eye> -
Glaucoma, angle-closure
damage to the nerve in the eye caused by pressure inside the eye rising rapidly because fluid cannot drain out -
Glaucoma, narrow-angle
see glaucoma, angle-closure -
Glaucoma, open-angle
damage to the nerves in the eye caused by high pressure due to clogging of fluid drainage canals -
Glioma
a type of brain tumour that begins in ‘glial’ cells (the cells that surround and support nerve cells) -
Glossodynia
burning or tingling sensation in or around the mouth -
Glucose
sugar -
Gluteal region
buttocks -
Glycosylated haemoglobin (HbA1c)
the proportion of haemoglobin in the blood that has glucose attached. HbA1c indicates how well blood glucose is controlled -
Gout
high levels of uric acid in the blood causing symptoms especially painful inflammation in the joints -
Graft versus host disease
when transplanted cells attack the body <because the transplanted tissue or organ regards the patient’s tissue as ‘foreign’ and attacks the body> -
Granulation
wound healing -
Granulation, hypertrophic
excessive production of tissue during wound healing -
Granulocytes
a type of white blood cell -
Guillain-Barré syndrome
an immune system disorder that causes nerve inflammation <and can result in pain, numbness, muscle weakness and difficulty walking> -
Gynaecomastia
abnormal breast enlargement