sodium phosphate

Action and Spectrum

Actions and Spectrum: 

sodium phosphate solutions are hypertonic. When administered rectally, they draw water into the colon through osmosis. The osmotic effect leads to an influx of water into the bowel, increasing the fluid content in the colon. This results in distension and elevated intraluminal pressure. 

sodium phosphate solutions also have an irritant effect on the intestinal mucosa. This irritation contributes to the stimulation of peristalsis, further aiding in bowel movements. 

The combination of increased water content and stimulation of peristalsis softens stool, making it easier to pass. 

Spectrum of Activity: 

sodium phosphate rectal solutions are commonly used for bowel cleansing before medical procedures such as colonoscopy or surgery. The goal is to achieve a clear view of the bowel for diagnostic or surgical purposes. While sodium phosphate solutions are not typically used as routine or long-term laxatives, they may be recommended for short-term relief of constipation under the guidance of a healthcare professional. 

Drug Interaction

Adverse Reaction

Frequency not defined 

Pruritus 

Hyperphosphatemia 

Hypokalemia 

Metabolic acidosis 

Vomiting 

Abdominal distension 

Hypersensitivity 

Dehydration 

Hypocalcemia 

Hypernatremia 

Nausea 

Abdominal pain 

Black Box Warning

None 

Contraindication / Caution

Contraindications/caution: 

Contraindications: 

Severe Renal Impairment 

Dehydration 

Electrolyte Imbalances 

Caution: 

• Renal Impairment: When using sodium phosphate rectal solutions, individuals with mild to moderate renal impairment may require dose adjustments or close monitoring. Severe renal impairment is generally a contraindication. 

• Dehydration Risk: sodium phosphate solutions have osmotic effects that can draw water into the intestines.  

• Age Considerations: Caution is warranted when considering the use of sodium phosphate rectal solutions in elderly individuals, as they may be more susceptible to electrolyte imbalances and dehydration. 

• Electrolyte Imbalances: Individuals with conditions predisposing them to electrolyte imbalances, such as abnormal sodium or phosphate levels, should use sodium phosphate solutions with caution. 

• Heart Conditions: Patients with heart conditions, including congestive heart failure, may be at an increased risk of fluid retention. Caution is advised, and careful monitoring may be necessary. 

Pregnancy / Lactation

Pregnancy consideration: There was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.    

Pregnancy Category: C 

Lactation: Excretion of the drug in human breast milk is unknown; exercise caution due to the possibility of electrolyte imbalances or dehydration 

Pregnancy category: 

Category A: well-controlled and Satisfactory studies show no risk to the fetus in the first or later trimester. 

Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women. 

Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.    

Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.    

Category X: Drugs listed in this category outweigh the risks over benefits. Hence, these categories of drugs need to be avoided by pregnant women.    

Category N: There is no data available for the drug under this category

Pharmacology

Pharmacology: 

The pharmacology of sodium phosphate rectal solutions involves their osmotic and irritant effects on the gastrointestinal tract, leading to increased water retention in the bowel and stimulation of bowel movements. 

• Osmotic Effect: sodium phosphate solutions are hypertonic, meaning they have a higher solute concentration than the surrounding tissues. When administered rectally, they draw water into the colon through osmosis. 

• Increased Intraluminal Pressure: The osmotic effect increases the volume of liquid in the bowel, leading to distension and increased intraluminal pressure. 

• Stimulation of Peristalsis: The increased pressure and distension of the bowel stimulate peristalsis, the coordinated muscular contractions of the intestines, promoting the movement of stool through the colon. 

• Irritant Effect: sodium phosphate solutions also have an irritant effect on the intestinal mucosa, contributing to the stimulation of peristalsis and aiding in bowel movements. 

• Cleansing Effect: The combination of increased water content and stimulation of peristalsis results in a cleansing effect, promoting the evacuation of stool and waste material from the bowel. 

Pharmacokinetics: 

Absorption 

sodium phosphate is minimally absorbed from the gastrointestinal tract, and its primary action occurs within the colon. 

Distribution 

The effects of sodium phosphate are localized to the gastrointestinal tract, and systemic absorption is limited. 

Metabolism 

sodium phosphate does not undergo significant metabolism within the body. 

Elimination and Excretion 

Unabsorbed sodium phosphate is excreted in the feces. 

Adminstartion

Administration: 

Rectal administration 

The administration of sodium phosphate rectal solutions involves the introduction of the medication into the rectum for its therapeutic effects, typically as a laxative or for bowel cleansing. 

• Preparation: Remove the orange protective shield from the enema tip before insertion. 

• Insertion: Gently insert the enema tip into the rectum with steady pressure, using a slight side-to-side movement. The tip should point toward the navel. 

• Facilitate Insertion: The person receiving the enema can bear down, simulating a bowel movement, to help relax the muscles around the anus. 

• Avoid Force: Do not force the enema tip into the rectum to prevent injury. 

• Administration: Squeeze the enema bottle until nearly all liquid is dispensed. It’s not necessary to empty the bottle, as it contains more liquid than needed. 

• Retain Position: Remove the enema tip and maintain the position until the urge to evacuate is strong (usually 1-5 minutes). 

• Time Limit: Do not retain the enema solution for more than 10 minutes. 

• Temperature: Ensure the enema is at room temperature before use. 

Recommended positions: 

Left-Side Position: Rest your arms comfortably and bend your left knee while lying on your left side. 

Knee-Chest Position: Bend forward at the knees, then bring your head and upper body forward until your left side of the face rests on the ground, your left arm comfortably folded. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: sodium phosphate  

Why do we use sodium phosphate? 

sodium phosphate rectal solutions have several uses, primarily related to their osmotic and irritant effects on the gastrointestinal tract. 

• Bowel Cleansing Before Procedures: sodium phosphate rectal solutions are frequently used for bowel cleansing before diagnostic procedures such as colonoscopy or surgery.  

• Constipation Relief: While not typically recommended for routine or long-term use, sodium phosphate rectal solutions may be used for short-term relief of constipation under the guidance of a healthcare professional. They promote bowel movements by increasing water content and stimulating peristalsis. 

• Evacuation of the Bowel: The irritant and osmotic effects of sodium phosphate solutions help induce bowel evacuation. 

• Preparation for Gastrointestinal Surgery: sodium phosphate rectal solutions may be used as part of the bowel preparation regimen before gastrointestinal surgery. This helps ensure that the bowel is adequately cleansed before the procedure.