Constipation phosphates

Adverse effects of calcium-containing phosphate binders, as well as sevel-amer and lanthanum, include constipation, diarrhea, nausea, vomiting, and abdominal pain. The risk of hypercalcemia is also a concern. To avoid potential drug interactions, phosphate binders should be administered 1 hour before or 3 hours after other oral medications. 

A variety of adverse effects have been reported following the use of antacids. If sodium bicarbonate is absorbed, it can cause systemic alkalization and sodium overload. Calcium carbonate may induce hypercalcemia and a rebound increase in gastric secretion secondary to the elevation in circulating calcium levels. Magnesium hydroxide may produce osmotic diarrhea, and the excessive absorption of Mg++ in patients with renal failure may result in central nervous system toxicity. Aluminum hydroxide is associated with constipation serum phosphate levels also may become depressed because of phosphate binding within the gut. The use of antacids in general may interfere with the absorption of a number of antibiotics and other medications. 

It is weak and slow reacting antacid. The aluminium ion relaxes smooth muscles, thus delays gastric emptying and causes constipation. It can also adsorb pepsin at pH > 3 but releases it at lower pH. It also prevents phosphate absorption. 

High doses of osmotically active agents produce prompt bowel evacuation (purgation) within 1-3 hours. The rapid movement of water into the distal small bowel and colon leads to a high volume of liquid stool followed by rapid relief of constipation. The most commonly used purgatives are magnesium citrate and sodium phosphate. 

Anileridine, ethyl l-(4-amino phenethyl)-4 phenylisonipecotate is available in the form of its dihydrochloride for oral administration and as the phosphate for injection (Leritine ). Its analgesic potency is intermediate between that of meperidine and morphine. Similar to meperidine, it exerts mild antihistaminic and spasmolytic effects, but it is devoid of the constipating effect of opiates. Sedative and direct hypnotic effects are similar to those of meperidine but less than those of morphine. 

Mrs TY could have codeine phosphate prescribed four times a day on a regular basis. Elderly patients are prone to experiencing side-effects, including constipation and drowsiness, from large doses of codeine. For this reason, it would be advisable for the dose to remain at 30 mg four times a day for now, rather than increasing to 60 mg four times a day straight away. Once this has been tried, the dose could be further increased if necessary, as the maximum dose is 240 mg per day. Codeine phosphate can be taken every 3-4 hours if required. 

Aluminium hydroxide reacts with HCl to form aluminium chloride this in turn reacts with intestinal secretions to produce insoluble salts, especially phosphate. The chloride is released and reabsorbed so systemic acid-base balance is not altered. It tends to constipate. Sufficient aluminium may be absorbed from the intestine to create a risk of encephalopathy in patients with chronic renal failure. Hypophosphataemia and hypophosphaturia may result from impaired absorption due to phosphate binding. 

Sodium phosphates are considered to be dangerous (1), particularly because of their effects on electrolyte balance. An oral solution of sodium phosphates (dibasic sodium phosphate + monobasic sodium phosphate) is used as a laxative for the relief of occasional constipation and is used as part of a bowel-cleansing regimen in preparing patients for surgery or colonoscopy. 

Spinrad S, Sztern M, Grosskopf Y, Graff E, Blum I. Treating constipation with phosphate enema an unnecessary risk. Isr J Med Sci 1989 25(4) 237-8. 

Antacids neutralize gastric acid, inactivate pepsin, and bind bile salts. Aluminum-containing antacids also suppress HP and enhance mucosal defense. ° G1 adverse effects are most common with antacids and are dose dependent. Magnesium salts cause an osmotic diarrhea, whereas aluminum salts cause constipation. Diarrhea usually predominates with magnesium/aluminum preparations. Aluminum-containing antacids (except aluminum phosphate) form insoluble salts with dietary phosphorus and interfere with phosphorus absorption. Hypophosphatemia occurs most often in patients with low dietary phosphate intake (e.g., malnutrition or alcoholism). Combined treatment with sucralfate may amplify the hypophosphatemia and the potential for aluminum toxicity (see section on sucralfate). 

Disopyramide phosphate is used orally for the treatment of certain ventricular and atrial arrhythmias. Despite its structural dissimilarity to procainamide (Fig. 26.10), its cardiac effects are very similar. Disopyramide is rapidly and completely absorbed from the gastrointestinal tract. Peak plasma level is usually reached within 1 to 3 hours, and a plasma half-life of 5 to 7 hours is common. Approximately half of an oral dose is excreted unchanged in the urine. The remaining drug undergoes hepatic metabolism, principally to the corresponding N-dealkylated form. This metabolite retains approximately half the antiarrhythmic activity of disopyramide and also is subject to renal excretion. Adverse effects of disopyramide frequently are observed. These effects are primarily anticholinergic in nature and include dry mouth, blurred vision, constipation, and urinary retention. 

Gastrointestinal system Nausea and vomiting Diarrhea Constipation Anorexia Stomatitis (waste buildup) Bleeding (waste buildup, impaired clotting) Parenteral nutrition (if indicated) Enteral nutrition (if indicated) Dietary restriction of potassium (40 mEq or as ordered), sodium, phosphate based on values of labwork Protein intake based on need (0.6-2 g/kg/day)... 

Calcium is the most abundant essential mineral in the human body, 99% being located in the bones and teeth. Caldum salts have been used therapeutically in many conditions, such as lactose intolerance, osteoporosis, premenstrual syndrome, colorectal cancer, kidney stones, and multiple sclerosis. Calcium supplementation has long been regarded as a fimdamental part of the prevention and treatment of postmenopausal bone loss. Several other health benefits have also been suggested, including improvements in blood pressure and serum cholesterol. Its adverse effects include constipation, bloating, and gas [Ifi ], as well as interference with the absorption of phosphate [17. ... 

A 13-year-old boy with Costello syndrome (neonatal macrosomia with subsequent slow growth, developmental delay, coarse facial dysmorphisms, gingival hyperplasia, skeletal anomalies, and hypertrophic cardiomyopathy) and chronic constipation developed signs and symptoms of acute renal insufficiency, after having received four phosphate-containing enemas (125 ml containing sodium... 

Antacids are substances used to neutralize excess stomach acid (HCl). Some antacids are mixtures of aluminum hydroxide and magnesium hydroxide. These hydroxides are not very soluble in water, so the levels of available OH are not damaging to the intestinal tract. However, aluminum hydroxide has the side effects of producing constipation and binding phosphate in the intestinal tract, which may cause weakness and loss of appetite. Magnesium hydroxide has a laxative effect. These side effects are less likely when a combination of the antacids is used. 

A five-year-old boy weighing 20 kg presented with severe constipation. He was treated with two paediatric-sized phosphate enemas. Approximately 20 min after enema administration, the boy became increasingly lethargic and complained of dizziness. Laboratory tests revealed marked elevation of serum phosphate and decreased calcium levels. This condition was managed with intravenous fluids and calcium gluconate. Normalisation of serum phosphate and calcium levels occurred within 5 h [75 ]. 

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