In
medicine, a contraindication is a condition (a situation or factor) that serves as a reason not to take a certain medical treatment due to the harm that it would cause the patient. Contraindication is the opposite of
indication
Indication may refer to:
* A synonym for sign
* Human interface, highlighting the single object pointed to as a cursor is moved, without any other user action such as clicking, is indication
* Indication (medicine). A valid reason to use a certain ...
, which is a reason to use a certain treatment.
Absolute contraindications are contraindications for which there are no reasonable circumstances for undertaking a course of action (that is, overriding the prohibition). For example:
* Children and teenagers with viral infections should not be given
aspirin because of the risk of
Reye syndrome.
* A person with an
anaphylactic food allergy should never eat the food to which they are allergic.
* A person with
hemochromatosis should not be administered iron preparations.
* Some medications are so
teratogenic that they are absolutely contraindicated in pregnancy; examples include
thalidomide and
isotretinoin.
Relative contraindications are contraindications for circumstances in which the patient is at higher risk of complications from treatment, but these risks may be outweighed by other considerations or mitigated by other measures. For example, a pregnant person should normally avoid getting
X-rays, but the risk from
radiography may be outweighed by the benefit of diagnosing (and then treating) a serious condition such as
tuberculosis.
Another principal pair of
terms for ''relative contraindications'' versus ''absolute contraindications'' is ''cautions'' versus ''contraindications'', or (similarly) ''precautions'' versus ''contraindications'': these pairs of terms are respectively synonymous. Which pair is used depends on
nomenclature enforced by each organization's
style. For example, the ''
British National Formulary'' uses the ''cautions versus contraindications'' pair, and various U.S.
CDC webpages use ''precautions'' versus ''contraindications''. The logic of the latter two styles is the idea that readers must never be confused: the word ''contraindication'' in that
usage ''always'' is meant in its absolute
sense, providing unmistakable
word-sense disambiguation.
See also
* ''
Classification of Pharmaco-Therapeutic Referrals''
*
Drug reaction testing Drug reaction testing uses a genetic test to predict how a particular person will respond to various prescription and non-prescription medications. It checks for genes that code for specific liver enzymes which activate, deactivate, or are influenc ...
*
Indication (medicine)
In medicine, an indication is a valid reason to use a certain test, medication, procedure, or surgery. There can be multiple indications to use a procedure or medication. An indication can commonly be confused with the term diagnosis. A diagnosis ...
*
Never events
References
{{wiktionary
Medical terminology