Effect of phosphate binder therapy on mortality in persons with chronic kidney disease

Aluminum phosphate

(aluminum orthophosphate, aluminum phosphate) - AlPO4, inorganic compound, aluminum salt of phosphoric acid. A solid, white crystalline substance, insoluble in water. Occurs in nature in the form of numerous minerals. It is formed in the form of a gelatinous precipitate when water-soluble aluminum salts are exposed to soluble phosphates.

It is used as a flux in the production of ceramics, an additive for cement, a high-temperature dehydrating agent, for the production of special types of glass, as a catalyst in organic synthesis. It is also used as a component for some baking powders in confectionery and in medicine as an antacid.

Chemical properties

Aluminum orthophosphate is an inorganic compound, a white, solid that is insoluble in water and poorly soluble in alcohol. The product dissolves well in nitric and hydrochloric acid . Aluminum Phosphate Formula: AlPO4. The chemical compound is found in various natural minerals. The substance is a reaction product of the action of water-soluble aluminum salts on soluble phosphates. This produces a white gelatinous precipitate.

There are 4 modifications of the Aluminum Phosphate formula, among which the most stable are: α-AlPO4 - with a hexagonal lattice and β-AlPO4 - with a hexagonal or cubic lattice. The chemical compound is quite stable and decomposes at very high temperatures (above 2000 degrees). Molecular weight = 121.9 grams per mole.

The substance is used as a flux in the production of ceramic products; added to cement during construction; used as a high-temperature dehydrating agent in the glass industry; as a catalyst during organic synthesis. Aluminum phosphate is used as a leavening agent in the manufacture of confectionery products. In medicine, the drug is prescribed as an antacid.

Trace aluminum, potentially toxic element

Pyelonephritis

4495 21 November

IMPORTANT!

The information in this section cannot be used for self-diagnosis and self-treatment.
In case of pain or other exacerbation of the disease, diagnostic tests should be prescribed only by the attending physician. To make a diagnosis and properly prescribe treatment, you should contact your doctor. Aluminum (mw 26.98) is one of the most common elements in the earth’s crust, but in the human body it is a trace element; the physiological concentrations of aluminum in various organs and tissues are at a very low level. The gastrointestinal tract is relatively impermeable to this element: absorption normally amounts to about 2% of incoming aluminum, the rest of the aluminum forms poorly soluble complexes (mainly with food phosphates) that are not absorbed. Aluminum easily binds to plasma proteins (including transferrin) and is quickly distributed throughout the body; 20% of plasma aluminum is in the form of free or complexed into small molecules. The main ways to remove aluminum that enters the blood are filtration into the urine in the glomeruli of the kidneys and excretion with bile. Impaired kidney function leads to increased accumulation of aluminum.

Aluminum is a potentially toxic element. The source of harmful effects may be an increased aluminum content in industrial dust, the ingress of industrial waste into tap water, or the use of certain medications and procedures. In medicine, the adsorbing, enveloping, antacid and analgesic properties of drugs containing aluminum (eg Almagel) are used; The information for such drugs usually indicates the possible toxic effect of aluminum. Aluminum may also be contained in elevated concentrations in parenteral nutrition preparations and albumin solutions, which is associated with the method of their industrial production and purification. Household sources of aluminum entering the body can be aluminum cookware, cosmetics, and deodorants. The most common cases of aluminum intoxication were observed in patients with chronic renal failure when exposed to aluminum-containing substances during treatment.

The mechanisms of the toxic effect of excess aluminum include interference with the metabolism of calcium, phosphorus, iron and other biologically active elements, and changes in the activity of enzyme systems. Important target organs for the pathological effects of aluminum are bones (aluminum replaces calcium at the mineralization front, disrupts the normal formation of osteoid, makes bone calcium less available for mobilization) and the brain (aluminum encephalopathy in severe intoxication). Aluminum is able to occupy calcium-binding sites in the parathyroid glands, which regulate phosphorus-calcium metabolism, causing a change in their physiological response. It has been shown that an increase in aluminum concentration can reduce the absorption of many elements and vitamins. Aluminum, which comes in excess quantities with industrial dust during breathing, accumulates in the lungs, causing fibrosis of the lung tissue with prolonged exposure. Great interest in aluminum metabolism was caused by the discovery of its accumulation in certain areas of the brain in Alzheimer's disease. Although the causal relationship between aluminum accumulation in the brain and neurofibrillary degeneration in Alzheimer's disease is unclear, and the accumulation may be secondary in nature, the role of aluminum as a risk factor in the development of Alzheimer's disease continues to be debated.

Serum. Patients with renal failure, due to impaired removal of aluminum from the blood, are potentially at risk of aluminum intoxication. The cause of intoxication may be exposure to aluminum-containing dialysis fluid, the use of oral phosphate binders, and albumin preparations with a high aluminum content. Manifestations of intoxication in severe cases may include osteomalacia and encephalopathy. Laboratory signs of the toxic effects of aluminum in dialysis patients include an abnormally low level of parathyroid hormone for the existing degree of renal failure, combined with a high level of aluminum in the blood serum. According to the literature, patients with signs of osteomalacia and encephalopathy usually have an intact parathyroid hormone level below 16 pmol/l and a serum aluminum level above 60 μg/l, patients without such symptoms have a parathyroid hormone level above 16 pmol/l and a serum aluminum level below 20 µg/l.

The recommended material for studying the status of aluminum in the body is serum or plasma. With normal kidney function, the aluminum content in the urine correlates with the level of aluminum entering the body. Aluminum levels in hair and nails reflect chronic exposure to this element, but they can be contaminated with aluminum through the use of water or detergents containing high aluminum content, or exposure to dust containing aluminum.

IMPORTANT!

The information in this section cannot be used for self-diagnosis and self-treatment. In case of pain or other exacerbation of the disease, diagnostic tests should be prescribed only by the attending physician. To make a diagnosis and properly prescribe treatment, you should contact your doctor.

Pharmacodynamics and pharmacokinetics

After entering the stomach, Aluminum Phosphate within 10 minutes increases the pH level to 3.5-5 and significantly reduces the activity of the pepsin . The substance does not cause alkalization of gastric juice, the acidity of the stomach contents remains at the same level, and does not stimulate secondary hypersecretion of hydrochloric acid . The medicine has an absorbent effect, eliminating viruses, bacteria, exotoxins , gases and endotoxins . After taking this medicine, a protective layer forms on the mucous membrane of the digestive tract.

Aluminum phosphate

Aluminum phosphate

(eng.
aluminum phosphate
) or
aluminum orthophosphate
,
aluminum phosphate , AlPO4
- aluminum salt of phosphoric acid. In medicine, it is an antacid.

Aluminum phosphate is the international nonproprietary name of the drug

Aluminum phosphate is the international nonproprietary name (INN) of the drug. According to ATC, aluminum phosphate belongs to the section “A02A Antacids”, group “A02AB Aluminum Preparations” and has the code A02AB03.

Aluminum phosphate - antacid

Aluminum phosphate, as an antacid, is a so-called “non-absorbable antacid”.
The effect of non-absorbable antacids develops more slowly than that of absorbed ones, but lasts longer, up to 2.5–3 hours. Another important advantage of non-absorbable antacids is the absence of the “acid rebound” phenomenon, which consists of an increase in the secretion of hydrochloric acid after the end of the drug’s effect (Bordin D.S.). Most of the aluminum phosphate gel is insoluble, but at less than 2.5 the aluminum phosphate gel turns into water-soluble ammonium chloride, part of which is able to dissolve, after which further dissolution of the aluminum phosphate is suspended. A gradual decrease in the acidity level of gastric contents to pH 3.0 does not lead to the occurrence of “acid rebound”: the use of aluminum phosphate gel does not lead to the appearance of secondary hypersecretion of hydrochloric acid. Colloidal aluminum phosphate binds endogenous and exogenous toxins, bacteria, viruses, gases formed as a result of putrefaction and pathological fermentation throughout the gastrointestinal tract, normalizing their passage through the intestines and thereby facilitating their removal from the body. Under its influence, pain sensations are also weakened (Vasiliev Yu.V.). Aluminum phosphate in a dose of 2.08 g is used in the treatment of moderate and infrequently occurring symptoms of gastroesophageal reflux disease (GERD), especially those associated with non-compliance with the recommended lifestyle (Recommendations of the Russian State Administration for the diagnosis and treatment of GERD, 2020).

The advantage of aluminum phosphate compared to other non-absorbable antacids containing aluminum

The level of aluminum absorption may be different for different drugs, which must be taken into account when determining the possible risk of side effects due to the fact that antacid drugs containing aluminum can cause hypophosphatemia in some patients, especially with prolonged use; in renal failure - encephalopathy, osteomalacia (with an aluminum level of more than 3.7 µmol/l), clinical symptoms considered characteristic of poisoning (with an aluminum concentration of more than 7.4 µmol/l).
The lower toxicity of aluminum phosphate, compared to aluminum hydroxide, is due to its greater resistance to dissolution and the formation of neutral complexes in the presence of acids usually found in food, which indicates the lower toxicity of aluminum phosphate (Vasiliev Yu.V.). With long-term use of drugs based on aluminum hydroxide, which interferes with the absorption of dietary phosphates in the intestine, hypophosphatemia, osteoporosis and osteomalacia may develop. This circumstance is associated with the limitation of the use of aluminum-containing antacids in children and pregnant women. The exception is aluminum phosphate, which does not affect phosphorus-calcium metabolism. Therefore, it can be prescribed to both pregnant women and nursing mothers, and children from birth. The use of aluminum phosphate may be preferable in elderly patients, who often have reduced bone density (Samsonov A.A., Odintsova A.N.).

Professional medical articles addressing the use of aluminum phosphate

• Vasiliev Yu.V. Modern antacid drugs in gastroenterological practice // Attending Physician. – 2004. – No. 4.
• Konorev M.R. Selection of the optimal antacid drug in clinical practice // Consilium Medicum. – 2003. Extra edition. – pp. 9–11.
• Lapina T.L. The importance of antacids in acid-dependent diseases // Breast Cancer. Diseases of the digestive system. – 2006. – Volume 8. – No. 2. – p. 114–116

On the website in the literature catalog there is a section “Antacids”, containing articles devoted to the treatment of diseases of the gastrointestinal tract with antacids

Medicines with the active ingredient aluminum phosphate

Currently, only one medicine with aluminum phosphate as the only active ingredient is registered in Russia - Phosphalugel.
Previously, Alfogel and Gasterin (also containing pectin) also had registration, but this has now expired. Hephal, a drug with the active ingredient aluminum phosphate, is produced in Belarus.

In some countries, medicinal products containing the following active ingredients are (and were previously approved for) sale:

• aluminum phosphate: Alfogel, Gelfos (Gelfos), Gelatum, Phosphalugel
• aluminum phosphate + simethicone: Alposim, Aluphagel
• aluminum phosphate + pectin: Gasterin.

Aluminum phosphate has contraindications, side effects and application features; consultation with a specialist is necessary. Some manufacturers do not recommend that pregnant women use drugs containing aluminum phosphate, as stated in the instructions (Tyutyunnik V.L., Elokhina T.B.). Back to section

Indications for use

Gel with Aluminum Phosphate is prescribed:

• for the treatment of gastric and duodenal ulcers during exacerbation;
• for chronic gastritis with increased or normal secretory function in the acute phase;
• patients with acute duodenitis , gastritis ;
• with erosion of the gastrointestinal mucosa;
• for the treatment of reflux esophagitis , hiatal hernia ;
• for enterocolitis , proctitis , sigmoiditis , diverticulitis ;
• to eliminate diarrhea after gastrectomy ;
• patients with indigestion , including after taking medications, chemotherapy , non-compliance with diet, neurotic origin;
• in acute or chronic pancreatitis (exacerbation phase);
• patients with intoxication and poisoning.

Links[edit]

• Dec, Corbridge. (2013). Phosphorus: chemistry, biochemistry and technology
  (6th ed.). CRC Press. ISBN 9781439840894.

Quotes [edit]

1. Patnaik will die. Handbook of Inorganic Chemicals
   . McGraw-Hill, 2002, ISBN 0-07-049439-8
2. ^ a b
   Corbridge, pp. 207-208
3. Corbridge, page 310
4. Tanaka, Y; and others. (2010). "Determination of structural chirality of berlinite and quartz by resonant x-ray diffraction with circularly polarized x-rays". Physical Review
   B.
   81
   (14): 144104. Bibcode: 2010PhRvB..81n4104T. DOI: 10.1103/PhysRevB.81.144104. ISSN 1098-0121.
5. Growing crystals from a piezoelectric α-quartz-like material, berlinite, Motchany AI, Chvanski PP, Annales de Chimie Science des Materiaux properties, 2001, 26, 199
6. ^ a b
   Greenwood, Norman N.;
   Earnshaw, Alan (1997). Chemistry of elements
   (2nd ed.). Butterworth-Heinemann. p. 527. ISBN 978-0-08-037941-8.
7. Wilson, S.T.; and others. (1982). "Aluminophosphate molecular sieves: a new class of microporous crystalline inorganic solids". Journal of the American Chemical Society
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   (4):1146–1147. DOI: 10.1021/ja00368a062. ISSN 0002-7863.
8. Kulprathipanja, S, ed. (2010-02-17). Zeolites in industrial separations and catalysis
   . John Wiley and Sons. DOI: 10.1002/9783527629565. ISBN 9783527325054.
9. Xu, R; and others. (2007). Chemistry of Zeolites and Related Porous Materials: Synthesis and Structure
   . John Wiley and Sons. paragraph 39. ISBN 9780470822333.
10. Jump up
    ↑ RJ, Crowther (2010).
    Vaccine adjuvants: preparation methods and research protocols
    . Humana. pp. 65–66, 82. ISBN 9781617371592.
11. ^ a b
    Schaefer, Christophe;
    Peters, Paul W.J.; Miller, Richard K. (2015). Medications in Pregnancy and Breastfeeding: Treatment Options and Risk Assessment
    . S. Schaefer, P. Peters, R. C. Miller (3rd ed.). paragraph 94. ISBN 9780124080782.
12. S, pratiksha; TM, Jamie (2018), Antacids
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13. Corbridge, page 1025
14. Roncal-Herrero, T; and others. (2009-12-02). "Precipitation of iron and aluminum phosphates directly from aqueous solution as a function of temperature from 50 to 200 °C." Crystal Growing and Design
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15. Lagno, F; and others. (2005). "Synthesis of hydrated aluminum phosphate, AlPO 4 1.5H 2 O (AlPO4-H3), by controlled reaction crystallization in a sulfate medium." Industrial and Engineering Chemical Research
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Reviews

Several reviews about Aluminum Phosphate preparations:

• “... I have been taking this drug for a long time, it helps me cope with heartburn and nausea after eating, and does not cause side effects”;
• “...I always have this medicine in my medicine cabinet, I drink it periodically, as the doctor prescribed. Recently I was poisoned by something, so the medicine even helped me here”;
• “... I like the medicine, improvements come as soon as I start taking it. I take it for reflux, stomach and intestinal problems. The only thing is that it can cause constipation, for such a case I always have a laxative with me.”