Saline Laxatives
Class: Cathartics and Laxatives
ATC Class: A06AX02
VA Class: GA200
CAS Number: 124-38-9
Brands: Ceo-Two, Fleet Enema, Fleet Pedia-Lax, OsmoPrep, Phillips' Milk of Magnesia
Warning
- Renal Effects Associated with Oral Sodium Phosphates Preparations
Renal failure, acute phosphate nephropathy, and nephrocalcinosis reported rarely with oral sodium phosphates preparations (e.g., oral solution, OsmoPrep tablets) used for bowel cleansing. Often resulted in permanent renal function impairment and sometimes required long-term dialysis. (See Renal Effects under Cautions.)
Risk of acute phosphate nephropathy may be increased in patients with increased age (>55 years of age), hypovolemia, increased bowel transit time (e.g., bowel obstruction), active colitis, baseline renal disease, or known or suspected electrolyte disturbances (e.g., dehydration), and in patients receiving drugs that affect renal perfusion or function (e.g., diuretics, ACE inhibitors, angiotensin II receptor antagonists, possibly NSAIAs).
Importance of adherence to recommended dosage and dosing regimen.
Introduction
Laxatives containing magnesium cations or phosphate anions.
Uses for Saline Laxatives
Constipation
Used to relieve occasional constipation.
Use of saline laxatives for simple constipation is seldom necessary or desirable; bulk-forming laxatives are drugs of choice.
Do not use rectal suppositories or enemas if oral laxatives are effective.
Mild saline laxatives (e.g., oral magnesium hydroxide, milk of magnesia) have been used to treat constipation during pregnancy or the puerperium; bulk-forming laxatives or stool softeners preferred.
Used rectally, after administration of a stool softener or mineral oil, to evacuate the impacted colon in the treatment of constipation associated with stricture of the colon or fecal impaction. Alternatively, administer phosphate-containing saline enemas rectally after manual disimpaction to promote evacuation of fecal impactions.
Bowel Cleansing
Used orally and/or rectally (as suppositories or enemas) to empty the bowel prior to surgery or radiologic, proctoscopic, or endoscopic procedures, when thorough evacuation is essential.
FDA recommends using oral sodium phosphates preparations for bowel cleansing only when a prescription for such use has been issued by a clinician. (See Renal Effects under Cautions.)
Poisonings
May hasten removal of some poisons† from the GI tract after inducing emesis or performing gastric lavage. Not for use after poisonings with ingested acids or alkalies. Magnesium laxatives should not be used to remove poisons that produce CNS depression or renal function impairment.
Saline Laxatives Dosage and Administration
General
- Bowel Cleansing
Patients must drink sufficient quantities of clear fluids (minimum of 1.9–3.4 L per regimen, depending on the specific regimen). Use IV hydration in a hospital setting for fragile patients with inadequate home support or who are unable to drink an appropriate fluid volume. (See Fluid Intake under Cautions.)
Administration
Administer magnesium-containing saline laxatives orally as chewable tablets, suspensi.
