II. Indications
- Functional Constipation
- Colonoscopy preparation
III. Contraindications
IV. Mechanism
- Poorly absorbed, hyperosmolar agents
- Increases intestinal retention of water, stimulating stool passage
- Also, increases renal excretion of Hydrogen Ion, in place of the reabsorption of Sodium ions
V. Complications
- Hypocalcemia (phosphate Overdose)
VI. Medications: Sodium Salt Osmotic Laxatives
- Phopho-Soda (OsmoPrep, Visicol) 2 tablespoons in 4 ounces water orally
- Fleets Enema (Sodium phosphate) 133 ml enema (adult) or 66 ml enema (pediatric)
- Pink Lady Enema (1/2 Fleet Enema, 100 ml Docusate, 60 ml Mineral Oil, 60 ml Magnesium Citrate)
- Alternative agents
- Tap Water Enema
VII. Dosing: Sodium Phosphate Enema
-
General
- Onset of action: 2 to 5 minutes
- Attempt to retain enema for 15 to 30 minutes before stooling
- Adults (and age >12 years)
- One adult enema (133 ml) per Rectum
- Sodium phosphate may be used orally up to 45 ml/24 hours
- Risk of serious Electrolyte abnormalities or Renal Failure with higher doses or recurrent use
- Children: 2.5 ml/kg (up to 133 ml/dose)
VIII. Dosing: OsmoPrep
- Indicated prior to Colonoscopy
- Dispense 32 OsmoPrep tabs (1.5 g/tab)
- Evening before procedure
- Take 4 tabs orally with 8 oz clear fluid every 15 min for total of 20 tabs (5 doses in 75 min, 40 oz fluid)
- Day of procedure (starting 3 to 5 hours before)
- Take 4 tabs orally with 8 oz clear fluid every 15 min for total of 12 tabs (3 doses in 45 min, 24 oz fluid)
IX. Technique: Protocol for those who cannot Retain Enema (e.g. Dementia, Traumatic Brain Injury)
- Place Foley Catheter inserted into Rectum and slowly inflated
- Infuse enema liquid into Foley Catheter using Toomey syringe
- Tilt head of bed down to 15 to 30 degrees (trendelenburg position)
- Leave the Foley Catheter and balloon in place for 15 to 20 minutes to allow adequate enema retention time
- Prepare for rapid outflow of stool contents (pads and other protection on bed)
- Deflate the balloon and remove the Foley Catheter (standing to side)
- Fisher and Swaminathan in Swadron (2022) EM:Rap 22(11): 7-8
X. Adverse Effects
- Acute phosphate nephropathy (FDA Black Box Warning)
- Risk of permanent impact on Renal Function following use
- Risk Factors
- Diabetes Mellitus
- Age over 65 years
- Dehydration
- Concurrent NSAID, ACE Inhibitor, ARB or Diuretic
- Prevention of Renal Function impact
- Consider alternative Bowel Preparation if risk factors above
- Maintain clear fluid intake to replace fluid losses from Diarrhea
- Rectal Wall Trauma
- Abdominal Pain
- Abdominal Distention
- Nausea
- Hyperphosphatemia
- Hypocalcemia
- Hypokalemia
XI. Safety
- Pregnancy Category C
- Unknown safety in Lactation (but not typically absorbed)
XII. Drug Interactions
- Agents that decrease renal perfusion
XIII. Resources
XIV. References
- (2023) Management of Constipation, Presc Lett, #390108
- Hamilton (2020) Tarascon Pocket Pharmacopoeia
Images: Related links to external sites (from Bing)
Related Studies
fleet enema (on 9/12/2022 at Medicaid.Gov Survey of pharmacy drug pricing) | ||
FLEET ENEMA | Generic OTC | $0.01 per ml |
osmoprep (on 1/1/2022 at Medicaid.Gov Survey of pharmacy drug pricing) | ||
OSMOPREP TABLET | $8.02 each |
Ontology: sodium phosphate (C0074757)
Definition (NCI) | An inorganic compound used as a laxative, dietary supplement and for electrolyte-replacement purposes. Phosphate, a predominant intracellular anion, plays an important role in energy storage, osteoblastic and osteoclastic activities, regulating serum calcium concentrations, and numerous cellular phosphate-transfer reactions. Sodium phosphate increases fluidity of the intestinal contents by retention of water by osmotic forces, thereby indirectly inducing intestinal smooth muscle constriction. Sodium phosphate is also used in the renal excretion of hydrogen ions while promoting the reabsorption of sodium ions. |
Concepts | Pharmacologic Substance (T121) , Inorganic Chemical (T197) |
MSH | C018279 |
SnomedCT | 387399001, 71584004 |
English | sodium phosphate, sodium phosphate (medication), enemas sodium phosphate, mineral supplements sodium phosphate, sodium phosphate [Chemical/Ingredient], phosphates sodium, phosphate sodium, Sodium Phosphate, Phosphosoda, Hemisodium Phosphate, sodium Phosphate, SODIUM PHOSPHATE, Sodium phosphate (substance), phosphoric acid, sodium salt, Sodium phosphate, Sodium phosphate (product), Sodium Phosphates |
Spanish | fosfato de sodio (sustancia), fosfato de sodio (producto), fosfato de sodio |
Ontology: Sodium Phosphates - Enema (C0773869)
Concepts | Clinical Drug (T200) |
English | SODIUM PHOSPHATE,MONOBASIC/SODIUM PHOSPHATE,DIBASIC RECTAL ENEMA (ML), Sodium Phosphate & Biphosphate Enema, SODIUM PHOSPHATE,MONOBASIC/SODIUM PHOSPHATE,DIBASIC @ @ ENEMA (ML), SODIUM PHOSPHATE,MONOBASIC/SODIUM PHOSPHATE,DIBASIC ENEMA (ML), NA PHOS,M-B/NA PHOS,DI-BA ENEMA (ML), SODIUM PHOSPHATE,MONOBASIC/SODIUM PHOSPHATE,DIBASIC@@RECTAL@ENEMA (ML), NA PHOS,M-B/NA PHOS,DI-BA RECTAL ENEMA (ML), sodium phosphate & biphosphate enema, enema phosphates sodium, sodium phosphate enema, Sodium Phosphates - Enema |
Ontology: PHOSPHO-SODA (C0982341)
Concepts | Pharmacologic Substance (T121) |
English | phospho-soda, phospho soda, PHOSPHO-SODA |