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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.
D
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Dander
shed skin and hair -
Decompensated heart failure
see heart failure, decompensated -
Decompensated liver disease
see liver disease, decompensated -
Deep vein thrombosis (DVT)
blood clot in a deep vein, usually in the leg -
Delirium
confusion -
Deltoid muscle
muscle covering the shoulder joint -
Delusion
false beliefs -
Dementia
loss of intellectual function -
Demyelinating polyneuropathy
a neurological disorder characterised by progressive weakness and loss of sensation in the legs and arms -
Demyelination
breakdown of the covering around nerve fibres <which can affect brain activity, muscle control and sensations> -
Depot injection
a type of injection where the medicine is prepared so that it is absorbed by the body very slowly -
Dermatitis
inflammation of the skin -
Dermatitis, atopic
see eczema, atopic -
Dermatology
the treatment of skin conditions -
Desquamation
shedding of the upper layers of the skin -
Diabetic foot infection
infection that occurs in the feet of people with diabetes -
Diabetic ketoacidosis
a serious complication of diabetes with high levels of ketones in the blood <include relevant symptoms if needed> -
Diabetic peripheral neuropathy
damage to the nerves in the extremities that can occur in people with diabetes -
Diabetic precoma
a dangerous condition that can occur in diabetes -
Dialysis
technique for removing unwanted substances and excess fluid from the blood <when the kidneys do not work well enough> -
Dialysis, peritoneal
type of dialysis <involving circulating fluid into the abdomen and then allowing the fluid to flow out> -
Diaphoresis
excessive sweating -
Diaphragm
the main breathing muscle under the lungs -
Diastolic blood pressure
see blood pressure, diastolic -
Digital ulcers
see ulcers, digital -
Dilate
widen; expand -
Diplopia
double vision -
Disease-modifying (drugs or therapy)
treatment that changes the progress of a <long-term> disease -
Dissociation (psychiatry)
feeling disconnected from emotions and physical surroundings -
Distension
swelling -
Diuretic
a medicine that increases urine production <and reduces build up of water in the body> <and lowers blood pressure> -
Diverticulitis
a disease affecting the gut -
DNA
genetic material -
Dopamine
see neurotransmitter -
Dormant
inactive -
DRESS (drug rash with eosinophilia and systemic symptoms)
a severe reaction affecting the skin, blood and internal organs -
Ductus arteriosus, patent
a condition where the blood vessel that allows blood to bypass the baby's lungs before birth fails to close after birth. This causes heart and lung problems in the baby. -
Duodenitis
inflammation of the duodenum, the part of the gut leading out of the stomach -
Duodenum
the part of the gut leading out of the stomach -
Dysaesthesia
unpleasant and abnormal feeling when touched -
Dysarthria
difficulty speaking -
Dysgeusia
taste disturbance -
Dyskinesia
difficulty controlling movement -
Dyslipidaemia
abnormal levels of fat in the blood -
Dysmenorrhoea
period pains -
Dyspepsia
indigestion -
Dysphagia
difficulty swallowing -
Dysphonia
changes in the sound or tone of the voice -
Dysplasia
presence of abnormal cells <which may become cancerous> -
Dyspnoea
difficulty breathing -
Dystonia
involuntary muscle contractions -
Dysuria
painful urination