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(ī-ŏn′ĭk) [Gr. ion, going] Pert. to ions.


(ī-ō-nĭ-zā′shŭn) The process of adding or subtracting an electron from an atom. In radiology, ionization is the most common cause of radiobiological damage.


(ī′ŏ-nīz″) To separate into ions.


Intraoperative neurophysiological monitoring.


(ī-ŏn′ō-jĕn) [Gr. ion, going, + gennan, to produce] Anything that can be ionized.


(ī-ŏn′ă-fawr″) A compound that binds and carries metallic ions across cellular membranes.


(ī″ŏn-ŏ-trō′pĭk) [″ + ″] Having an influence on glutamate-gated cell surface receptors, i.e., on cell membrane channels that open or close in the presence of ions.


(ī″ont″ŏ-fĕ-rē′sĭs) [Gr. iōn, iont-, going + -phoresis] 1. The introduction of an electric current into a salt solution, causing migration of the metal (positive) ion to the negative pole and the radical (negative) ion to the positive pole. 2. The introduction of various ions into tissues through the skin by means of electricity. SYN: ionic medication; ionotherapy; iontotherapy. SEE: electrical patch.

pilocarpine i. Sweat test.


intraocular pressure.


(ī″ō-fĕn′dĭ-lāt) A radiopaque contrast medium used in myelography.


intraoperative quick assay of intact parathyroid hormone.


intraperitoneal; isoelectric point


independent practice association; International Psychogeriatric Association.


(ĭp′ĕ-kăk) A drug that induces vomiting. For many years, it was used to help empty the upper gastrointestinal tract after toxic ingestions and accidental overdoses. It no longer is used for this purpose in hospitals, where activated charcoal and whole bowel irrigation have proved to be more effective and better tolerated. The drug is derived from the dried root of ipecacuanha, a plant that is native to Brazil. It typically is given as a syrup.

IPEX syndrome

[Abbr. of Immune dysregulation, polyendocrinopathy, enteropathy, X-linked] A rare X-linked disorder caused by dysfunction of regulatory T cells. Common symptoms include intestinal malabsorption, rashes, recurrent infections, and early-onset diabetes mellitus.


interpupillary line.

ipodate sodium

A radiopaque contrast medium used in radiographical studies of the gallbladder.


intermittent positive-pressure breathing.


intermittent positive-pressure ventilation.

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