What are the intravenous (IV) options for treating diarrhea?

From the Guidelines

For patients with diarrhea, the primary treatment option is oral rehydration with reduced osmolarity oral rehydration solution (ORS) as the first-line therapy for mild to moderate dehydration, as recommended by the 2017 Infectious Diseases Society of America clinical practice guidelines 1.

IV Options for Diarrhea

When oral rehydration is not possible or effective, IV options can be considered. The following are some IV options for diarrhea:

• IV fluid replacement with lactated Ringer's solution or normal saline to correct dehydration and electrolyte imbalances, as recommended by the 2017 Infectious Diseases Society of America clinical practice guidelines 1.
• IV antibiotics, such as ciprofloxacin (400mg IV every 12 hours) or metronidazole (500mg IV every 8 hours), for severe bacterial diarrhea, depending on the suspected pathogen.
• IV corticosteroids, like methylprednisolone (40-60mg daily), for severe inflammatory bowel disease flares causing diarrhea.
• IV antiemetics, such as ondansetron (4mg IV every 8 hours), for symptomatic relief in hospitalized patients with associated nausea and vomiting.

Key Considerations

• The underlying cause of diarrhea should be identified and treated specifically when possible, as these IV options primarily address symptoms and complications rather than the root cause in many cases.
• Patients with severe dehydration, shock, or altered mental status may require IV rehydration with isotonic fluids, such as lactated Ringer's or normal saline solution, as recommended by the 2017 Infectious Diseases Society of America clinical practice guidelines 1.
• The European Society for Medical Oncology (ESMO) clinical practice guidelines for diarrhea in adult cancer patients recommend oral rehydration therapy (ORT) for mild diarrhea and oral rehydration solutions (ORSs) for more severe diarrhea, with caution to avoid overhydration in elderly patients 1.

Treatment Approaches

• For mild diarrhea, ORT is generally appropriate, with ORSs, including standard WHO ORSs or commercial ORSs, recommended for more severe diarrhea 1.
• Rapid fluid resuscitation is not necessary in patients with mild to moderate hypovolaemia, and the rate of fluid administration should be greater than the rate of continued fluid losses 1.
• Loperamide can be started at an initial dose of 4 mg, followed by 2 mg every 2-4 hours or after every unformed stool, with a maximum daily dose of 16 mg 1.

From the Research

IV Options for Diarrhea

There are several IV options for treating diarrhea, particularly in cases of severe dehydration. The following are some of the options:

• Oral Rehydration Therapy (ORT) using commercially available oral solutions containing 45-75 mEq/l of Na(+) for children with mild-to-moderate dehydration 2
• Intravenous fluids, 60-100 ml/kg of 0.9% saline in the first 2-4 h to restore circulation for children with severe dehydration 2
• Normal Saline (NS) or Ringer Lactate (RL) for intravenous rehydration in children with acute diarrhea and severe dehydration, as both have been shown to be equivalent in terms of change in serum sodium from baseline 3
• 5% dextrose in 0.45% saline containing 20 mEq/l KCl over 24 h for isonatremic dehydration, 0.9% saline and 0.45% saline alternately in a 1:1 ratio in 5% dextrose containing 20 mEq/l KCl over 24 h for hyponatremic dehydration, and 5% dextrose in 0.2% saline containing 20 mEq/l KCl over 2-3 days for hypernatremic dehydration 2

Key Considerations

When selecting an IV option for diarrhea, it is essential to consider the type and severity of dehydration, as well as the patient's overall condition. For example:

• Oliguric patients with severe acidosis may require a physiological dose of bicarbonate to correct blood pH level to 7.25 2
• Patients who cannot tolerate ORT may require intravenous rehydration for the remainder of the deficit and maintenance 2
• The amount of Na(+) given to replace maintenance and deficit fluids varies with the forms of dehydration 2

Administration and Monitoring

Proper administration and monitoring of IV fluids are crucial to ensure effective treatment and prevent complications. This includes:

• Administering IV fluids in small quantities to replace losses of water and Na(+) over 6-8 h 2
• Monitoring serum sodium levels and adjusting the IV fluid composition as needed 3
• Providing age-appropriate diet as soon as tolerated 2