 Chemical Structure.png)
Physicochemical Properties
| Molecular Formula | MG(OH)2 |
| Molecular Weight | 58.32 |
| Exact Mass | 57.99 |
| CAS # | 1309-42-8 |
| PubChem CID | 73981 |
| Appearance |
Amorphous powder White, hexagonal crystals Granules |
| Density | 2.36g/cm3 |
| Boiling Point | 100ºC at 760mmHg |
| Melting Point | 350ºC ( Decomposes) |
| Flash Point | will not burn |
| Hydrogen Bond Donor Count | 2 |
| Hydrogen Bond Acceptor Count | 2 |
| Rotatable Bond Count | 0 |
| Heavy Atom Count | 3 |
| Complexity | 0 |
| Defined Atom Stereocenter Count | 0 |
| InChi Key | VTHJTEIRLNZDEV-UHFFFAOYSA-L |
| InChi Code | InChI=1S/Mg.2H2O/h;2*1H2/q+2;;/p-2 |
| Chemical Name | magnesium;dihydroxide |
| Synonyms | Magnesium hydroxide, ultrapure grade, 99%(KT); Magnesium dihydroxide, 99%(KT) |
| HS Tariff Code | 2934.99.9001 |
| Storage |
Powder-20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month |
| Shipping Condition | Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs) |
Biological Activity
| ADME/Pharmacokinetics |
Absorption, Distribution and Excretion About 15%-50% of magnesium hydroxide is absorbed very slowly through the small intestine. After oral administration, up to 50% of the magnesium hydroxide suspension may be absorbed as magnesium ions through the small intestines and then rapidly excreted in the urine through the kidneys. The unabsorbed drug is mainly excreted in the feces and saliva. The peak action and distribution of magnesium hydroxide are variable. Magnesium hydroxide is mainly excreted in the urine by the kidneys. Since the kidneys play a major role in its clearance, individuals with renal failure are at risk of hypermagnesemia with long term consumption as the appropriate amounts of magnesium may not be excreted. ALTHOUGH MG(OH)2 IS CLASSIFIED AS A NONSYSTEMIC ANTACID, 5 TO 10% OF MAGNESIUM CAN BE ABSORBED... ORDINARILY THE ABSORBED MAGNESIUM ION IS RAPIDLY EXCRETED BY KIDNEY. IN NORMAL PERSONS, ABSORPTION IS ATTENDED BY LITTLE OR NO DANGER OF SYSTEMIC ALKALOSIS, BUT URINE MAY BECOME ALKALINE. ...EMPTIED SLOWLY FROM THE STOMACH, PROLONGING ITS ANTACID ACTION. ...ABOUT 5-15% OF INGESTED MAGNESIUM IS ABSORBED, & THIS IS READILY EXCRETED IN THE URINE IF KIDNEY FUNCTION IS NORMAL. Metabolism / Metabolites Unless a patient is deficient in magnesium, very little is absorbed by the intestine. Overall, about 15%-50% of the magnesium hydroxide suspension is absorbed systemically. However, it does not undergo any metabolism as it is rapidly excreted in the urine. Biological Half-Life N/A |
| Toxicity/Toxicokinetics |
Protein Binding Magnesium hydroxide does not have any protein binding properties. Interactions ...MAGNESIUM HYDROXIDE MAY INTERFERE WITH ABSORPTION OF WARFARIN BY ALKALINIZING GASTROINTESTINAL CONTENTS. ...IT HAS BEEN DEMONSTRATED THAT MAGNESIUM HYDROXIDE SUSPENSION ACTUALLY ENHANCES THE ABSORPTION OF DICUMAROL...HIGHER PEAK SERUM LEVELS... ALKALINIZATION OF URINE CAN DECR EXCRETION OF VARIOUS WEAKLY BASIC DRUGS (EG QUINIDINE). MG(OH2) INCR ABSORPTION OF WARFARIN IN MAN & DECR ABSORPTION OF BARBITURATES IN RATS. Non-Human Toxicity Values LD50 Rat oral 8500 mg/kg LD50 Rat intraperitoneal 2780 mg/kg |
| References |
[1]. "Clinically significant drug interactions with antacids: an update." Drugs 71 (2011): 1839-1864. |
| Additional Infomation |
Magnesium dihydroxide is a magnesium hydroxide in which the magnesium atom is bound to two hydroxide groups. It has a role as an antacid and a flame retardant. Magnesium hydroxide is an inorganic compound. It is naturally found as the mineral brucite. Magnesium hydroxide can be used as an antacid or a laxative in either an oral liquid suspension or chewable tablet form. Additionally, magnesium hydroxide has smoke suppressing and flame retardant properties and is thus used commercially as a fire retardant. It can also be used topically as a deodorant or for the relief of canker sores (aphthous ulcers). Magnesium Hydroxide is a solution of magnesium hydroxide with antacid and laxative properties. Milk of magnesium exerts its antacid activity in low doses such that all hydroxide ions that enter the stomach are used to neutralize stomach acid. This agent exerts its laxative effect in higher doses so that hydroxide ions are able to move from the stomach to the intestines where they attract and retain water, thereby increasing intestinal movement (peristalsis) and inducing the urge to defecate. An inorganic compound that occurs in nature as the mineral brucite. It acts as an antacid with cathartic effects. See also: Magnesium Cation (has active moiety); Calcium carbonate; famotidine; magnesium hydroxide (component of); Aluminum hydroxide; magnesium hydroxide (component of) ... View More ... Drug Indication Magnesium hydroxide can be used as an antacid or a laxative depending on the administered dose. As an antacid, it is used for the temporary relief of heartburn, upset stomach, sour stomach or acid indigestion. As a laxative, it is used for the relief of occasional constipation by promoting bowel movements for 30 minutes and up to 6 hours. Mechanism of Action The suspension of magnesium hydroxide is ingested and enters the stomach. According to the amount ingested, the magnesium hydroxide will either act as an antacid or a laxative. Through the ingestion of 0.5-1.5 grams (in adults) the magnesium hydroxide will act by simple acid neutralization in the stomach. The hydroxide ions from the magnesium hydroxide suspension will combine with the acidic H+ ions of the hydrochloric acid made by the stomachs parietal cells. This neutralization reaction will result in the formation of magnesium chloride and water. Through the ingestion of 2-5 grams (in adults) the magnesium hydroxide acts as a laxative in the colon. The majority of the suspension is not absorbed in the intestinal tract and will create an osmotic effect to draw water into the gut from surrounding tissues. With this increase of water in the intestines, the feces will soften and the intraluminal volume of the feces will increase. These effects still stimulate intestinal motility and induce the urge to defecate. Magnesium hydroxide will also release cholecystokinin (CKK) in the intestines which will accumulate water and electrolytes in the lumen and furthermore increase intestinal motility. COMPD IS PRACTICALLY INSOL, & SOLUTION IS NOT EFFECTED UNTIL HYDROXIDE REACTS WITH HYDROCHLORIC ACID TO FORM MAGNESIUM CHLORIDE. ...MG(OH)2 INCREASES LOWER-ESOPHAGEAL SPHINCTER PRESSURE & ACID SECRETION IN HEIDENHAIN POUCHES. Laxatives containing magnesium cations or phosphate anions are commonly called saline laxatives. Their cathartic action is believed to result from osmotically mediated water retention, which then stimulates peristalsis. However, other mechanisms may contribute to their effects, including the production of inflammatory mediators. It also has been suggested that magnesium containing laxatives stimulate the release of cholecystolkinin, which leads to intraluminal fluid and electrolyte accumulation as well as to increased intestinal motility. /Saline laxatives, including magnesium hydroxide/ Therapeutic Uses Antacids; Cathartics MAGNESIA MAGMA ACTS AS ANTACID OR LAXATIVE, DEPENDING ON DOSAGE EMPLOYED. TEN ML...NEUTRALIZES APPROX 270 ML OF 0.1 NORMAL HYDROCHLORIC ACID. ...OFTEN USED IN COMBINATION WITH ALUMINUM HYDROXIDE GEL SINCE IT TENDS TO OVERCOME MILD CONSTIPATING EFFECTS OF LATTER &...CONTRIBUTES ITS OWN ANTACID EFFECT. WHEN THE DOSE IS IN EXCESS OF THAT REQUIRED TO NEUTRALIZE THE ACID, INTRAGASTRIC PH MAY REACH 8 OR 9. ACID REBOUND FOLLOWING MG(OH)2 IS CLINICALLY INSIGNIFICANT. ...USED MAINLY FOR...LAXATIVE PROPERTIES, THE DOSE & FREQUENCY OF ADMIN ARE DETERMINED BY NUMBER OF SUBSTITUTIONS FOR ALUMINUM OR CALCIUM SALTS THAT RESULT IN NORMAL STOOL CONSISTENCY. For more Therapeutic Uses (Complete) data for MAGNESIUM HYDROXIDE (10 total), please visit the HSDB record page. Drug Warnings A DISADVANTAGE OF USE OF MG(OH)2 AS ANTACID IN SOME PATIENTS IS ITS CATHARTIC EFFECT. CONSEQUENTLY, MG(OH)2 IS USUALLY COADMINISTERED OR ALTERNATED WITH CONSTIPATING ANTACIDS, SUCH AS AL(OH)3 & CACO3, ALTHOUGH THE CONSTIPATING ACTION OF CACO3 IS NOW IN DOUBT. VET: ...RENAL DYSFUNCTION & REPEATED ADMIN CAN RESULT IN DANGEROUS DEGREE OF RETENTION, CAUSING NEUROLOGICAL, NEUROMUSCULAR, & CARDIOVASCULAR IMPAIRMENT. IN PT WITH RENAL DISEASE, MAGNESIUM RETENTION MAY RESULT FROM THE CHRONIC USE OF MAGNESIUM SALTS & CAN CAUSE NEUROLOGICAL, NEUROMUSCULAR, & CARDIOVASCULAR IMPAIRMENT. GASTRIC ACID SECRETION WAS STUDIED IN DUODENAL ULCER PT BEFORE & AFTER ADMIN OF MG(OH)2 & PLACEBO. GASTRIC ACID SECRETION WAS SIGNIFICANTLY GREATER AFTER MG(OH)2 ADMIN AS COMPARED TO BASAL VALUES; NO SIGNIFICANT DIFFERENCE WAS FOUND AFTER PLACEBO. For more Drug Warnings (Complete) data for MAGNESIUM HYDROXIDE (7 total), please visit the HSDB record page. Pharmacodynamics As an antacid, magnesium hydroxide suspension neutralizes gastric acid by reacting with hydrochloric acid in the stomach to form magnesium chloride and water. It is practically insoluble in water and does not have any effect until it reacts with the hydrochloric acid in the stomach. There, it decreases the direct acid irritant effect and increases the pH in the stomach leading to inactivation of pepsin. Magnesium hydroxide enhances the integrity of the mucosal barrier of the stomach as well as improving the tone of both the gastric and esophageal sphincters. As a laxative, the magnesium hydroxide works by increasing the osmotic effect in the intestinal tract and drawing water in. This creates distension of the colon which results in an increase in peristaltic movement and bowel evacuation. |
Solubility Data
| Solubility (In Vitro) | May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples |
| Solubility (In Vivo) |
Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples. Injection Formulations (e.g. IP/IV/IM/SC) Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline) *Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution. Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil) Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals). Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)] *Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution. Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline) Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline) Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline) Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil) Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Oral Formulations Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium) Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals). Oral Formulation 3: Dissolved in PEG400 Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose Oral Formulation 6: Mixing with food powders Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently. (Please use freshly prepared in vivo formulations for optimal results.) |
| Preparing Stock Solutions | 1 mg | 5 mg | 10 mg | |
| 1 mM | 17.1468 mL | 85.7339 mL | 171.4678 mL | |
| 5 mM | 3.4294 mL | 17.1468 mL | 34.2936 mL | |
| 10 mM | 1.7147 mL | 8.5734 mL | 17.1468 mL |