Mannitol is widely used in all fields of medicine, due to its beneficial ac
tions on the kidney and brain. Mannitol has been extensively used in cardia
c surgery since its infancy, and remains in common usage to day. Mannitol i
s mainly used for its effects on the kidneys, but it has actions on the bra
in, lungs, heart, gastrointestinal tract and the red cell. Mannitol also ha
s effects on free radicals and nitric oxide. As with virtually all treatmen
ts in medicine and surgery its use is not immune from side effects. The med
ical literature on mannitol over the past 30 years is considered.