bioavailability

American  

[bahy-oh-uh-vey-luh-bil-i-tee] / ˌbaɪ oʊ əˌveɪ ləˈbɪl ɪ ti /

noun

Biochemistry.

1. the extent to which a nutrient or medication can be used by the body.

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bioavailability British  

/ ˌbaɪəʊəˌveɪləˈbɪlɪtɪ /

noun

1. Also called: systemic availability.  the extent to which a drug or other substance is taken up by a specific tissue or organ after administration; the proportion of the dose of a drug that reaches the systemic circulation intact after administration by a route other than intravenous

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Other Word Forms

Derived Forms

• bioavailable
  adjective

Etymology

Origin of bioavailability

First recorded in 1965–70; bio- + available ( def. )

Example Sentences

“Systemic therapies have shown poor bioavailability in pancreatic tumors, limiting their effectiveness. Optune Pax is a fundamentally different treatment, utilizing a biophysical approach that targets the unique electrical properties of cancer cells.”

From Barron's • Feb. 12, 2026

"By contrast, small-molecule drugs that are designed to cross the blood-brain barrier are hydrophobic in nature, which limits their bioavailability, increases the risk of off-target binding, and is linked to side effects."

From Science Daily • Nov. 6, 2025

“If you take it orally, the bioavailability is in the range of 4–6%, which is terrible,” says Devinsky.

From Nature • Aug. 27, 2019

“Use of food as a way to increase bioavailability in patients with cancer could present problems and risks,” the drug's manufacturer, Janssen, said in a statement.

From Washington Post • Jun. 8, 2017

Bioequivalence studies measure whether a generic drug acts the same in the body as the name-brand drug; bioavailability studies measure how much drug gets into a patient’s system.

From Salon • Apr. 17, 2013