Magnesium citrate is a

magnesium preparation Magnesium salts are available as a medication in a number of formulations. They are used to treat magnesium deficiency, low blood magnesium, eclampsia, and several other conditions. Magnesium is important to health. Usually in lower dosages, ...

salt Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quant ...

form with

citric acid Citric acid is an organic compound with the chemical formula HOC(CO2H)(CH2CO2H)2. It is a colorless weak organic acid. It occurs naturally in citrus fruits. In biochemistry, it is an intermediate in the citric acid cycle, which occurs in ...

in a 1:1 ratio (1

magnesium Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic ...

atom Every atom is composed of a nucleus and one or more electrons bound to the nucleus. The nucleus is made of one or more protons and a number of neutrons. Only the most common variety of hydrogen has no neutrons. Every solid, liquid, gas, a ...

per citrate

molecule A molecule is a group of two or more atoms held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions which satisfy this criterion. In quantum physics, organic chemistry, and b ...

). The name "magnesium citrate" is ambiguous and sometimes may refer to other salts such as

trimagnesium citrate Magnesium citrate (3:2) (3 magnesium atoms per 2 citrate molecules), also called trimagnesium dicitrate, trimagnesium citrate, or the ambiguous name magnesium citrate. The substance magnesium citrate usually has water molecules attached to it. It ...

which has a magnesium:citrate ratio of 3:2. Magnesium citrate is used medicinally as a saline

laxative Laxatives, purgatives, or aperients are substances that loosen stools and increase bowel movements. They are used to treat and prevent constipation. Laxatives vary as to how they work and the side effects they may have. Certain stimulant, lubri ...

and to completely empty the bowel prior to a major surgery or

colonoscopy Colonoscopy () or coloscopy () is the endoscopic examination of the large bowel and the distal part of the small bowel with a CCD camera or a fiber optic camera on a flexible tube passed through the anus. It can provide a visual diagnosis ('' ...

. It is available without a prescription, both as a generic and under various brand names. It is also used in the pill form as a magnesium

dietary supplement A dietary supplement is a manufactured product intended to supplement one's diet by taking a pill, capsule, tablet, powder, or liquid. A supplement can provide nutrients either extracted from food sources or that are synthetic in order ...

. It contains 11.23% magnesium by weight. Compared to trimagnesium citrate, it is much more water-soluble, less alkaline, and contains less magnesium. As a

food additive Food additives are substances added to food to preserve Taste, flavor or enhance taste, appearance, or other sensory qualities. Some additives have been used for centuries as part of an effort to preserve food, for example vinegar (pickling), sal ...

, magnesium citrate is used to regulate acidity and is known as

E number E numbers ("E" stands for "Europe") are codes for substances used as food additives, including those found naturally in many foods such as vitamin C, for use within the European Union (EU) and European Free Trade Association (EFTA). Commonly ...

E345.

Mechanism of action

Magnesium citrate works by attracting water through the tissues by a process known as

osmosis Osmosis (, ) is the spontaneous net movement or diffusion of solvent molecules through a selectively-permeable membrane from a region of high water potential (region of lower solute concentration) to a region of low water potential (region ...

. Once in the intestine, it can attract enough water into the intestine to induce defecation. The additional water stimulates bowel motility. This means it can also be used to treat rectal and colon problems. Magnesium citrate functions best on an empty stomach, and should always be followed with a full (eight ounce or 250 ml) glass of water or juice to help the magnesium citrate absorb properly and help prevent any complications. Magnesium citrate solutions generally produce bowel movement in one half to three hours.

Use and dosage

The maximum upper tolerance limit (UTL) for magnesium in supplement form for adults is 350 mg of elemental magnesium per day, according to the

National Institutes of Health The National Institutes of Health, commonly referred to as NIH (with each letter pronounced individually), is the primary agency of the United States government responsible for biomedical and public health research. It was founded in the lat ...

(NIH). In addition, according to the NIH, total dietary requirements for magnesium from all sources (in other words, food and supplements) is 320–420 mg of elemental magnesium per day, though there is no UT for dietary magnesium.

Laxative

Magnesium citrate is used as a laxative agent. As a laxative syrup with a concentration of 1.745 g of magnesium citrate per fluid ounce, a typical dose for adults and children twelve years or older is between , followed immediately with a full glass of water. Consuming an adult dose of 10 oz of laxative syrup (@ 1.745 g/oz) implies a consumption of 17.45 g of magnesium citrate in a single dose resulting in a consumption of approximately 2.0 g of elemental magnesium per single dose. This laxative dose contains five times the recommended nutritional dose for children. Magnesium citrate is not recommended for use in children and infants two years of age or less.

Magnesium deficiency treatment

Although less common, as a magnesium supplement the citrate form is sometimes used because it is believed to be more bioavailable than other common pill forms, such as

magnesium oxide Magnesium oxide ( Mg O), or magnesia, is a white hygroscopic solid mineral that occurs naturally as periclase and is a source of magnesium (see also oxide). It has an empirical formula of MgO and consists of a lattice of Mg2+ ions and O2� ...

. But, according to one study, magnesium gluconate was found to be marginally more bioavailable than even magnesium citrate. Potassium-magnesium citrate, as a supplement in pill form, is useful for the prevention of kidney stones.

Side effects

Magnesium citrate is generally not a harmful substance, but care should be taken by consulting a healthcare professional if any adverse health problems are suspected or experienced. Extreme magnesium overdose can result in serious complications such as slow heart beat, low blood pressure, nausea, drowsiness, etc. If severe enough, an overdose can even result in

coma A coma is a deep state of prolonged unconsciousness in which a person cannot be awakened, fails to respond normally to painful stimuli, light, or sound, lacks a normal wake-sleep cycle and does not initiate voluntary actions. Coma patients exhi ...

or death.magnesium citrate
Cerner Multum. Drugs.com. 12 April 2009. However, a moderate overdose will be excreted through the kidneys, unless one has serious kidney problems. Rectal bleeding or failure to have a bowel movement after use could be signs of a serious condition.

References

External links

Saline laxatives
MedicineNet.
Magnesium citrate Patient Advice
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