Also found in: Dictionary, Thesaurus, Wikipedia.


An exceptionally large dose, as of a drug or vitamin.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


A very large or maximum dose beyond the known therapeutic range.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


A very large dose of a vitamin, taken by some people as a form of self-medication.
Mentioned in: Vitamin Toxicity
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
(13), vitamin A supplementation policies should be rethought, since studies have found no effect of supplementation on serum retinol in children after 2 months of megadose administration.
Considering the role of social representations in guiding behaviors, (35) it is believed that this valorization of vitamin A can stimulate the mothers' search for the megadose distributed in the BHUs.
Few studies have evaluated the use of vitamin A supplements by mothers, either in a megadose [16-18] or in higher doses [9, 19-23], and the serum concentrations in children at various points during a follow-up period.
Clinical data seem to suggest activity for at least some agents that merit further investigation--these include vitamin A, vitamin C, megadose vitamins and COX2 inhibitors.
Logo apos a coleta do sangue e do leite, foi administrada as participantes uma megadose de 200 000 UI (60 000 [micron]g) de retinil palmitato.
Indeed, one of the most memorable stories of big-wave history concerns Jock Sutherland, the Kelly Slater of the late '60s, high on a megadose of LSD, surfing huge Waimea Bay at night.
As yesterday's angry, young rockers pass thirty and go classical or limp, today's kids thrash it out in the basement--crudely, loudly with a megadose of upthrust middle finger attitude.
Treatment of optic neuritis with megadose corticosteroids.
While some dresses and ensembles easily cost more than $20,000, just gazing at these fashion wonders delivers a megadose of inspiration, adrenaline and beauty.
Superior service is where Span-Track supplied a megadose of improvement.
Jay Olshansky dismisses megadose vitamin supplements as "a way to make expensive urine."