Oral phosphate solutions are frequently used to prepare a patient for colonoscopy. These cleansing preparations can be associated with a number of risks.



(1) hyperphosphatemia

(2) phosphate nephropathy


Absolute contraindications:

(1) moderate to severe renal impairment

(2) bowel obstruction

(3) dehydration

(4) electrolyte disturbances

(5) heart failure


Relative contraindications:

(1) age > 57 years

(2) active colitis

(3) history of hypertension and atherosclerosis

(4) medications associated with phosphate nephropathy: NSAIDS, rennin-angiotensin inhibitors, diuretics

(5) cirrhosis


Recommendations for a patient with risk factors:

(1) Rehydrate if dehydrated and keep well-hydrated before, during and after use.

(2) Correct any electrolyte disturbances before use.

(3) Stop medications that may increase the risk of phosphate nephropathy.

(4) Monitor the patient afterwards with periodic evaluations for the next year (phosphate nephropathy may show an acute but delayed onset)..


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