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IV fluid monograph: adding potassium or glucose to plasmalyte

What's New

17/01/2024 This guidance now follows the same process as the PICU monograph 


To provide stepwise guidance for additions to maintenance fluid


Nursing & medical staff involved in the preparation and administration of intravenous infusions

  • Plasmalyte 148 + 10% glucose
  • Plasmalyte 148 + 15mmol Potassium (the final solution will have 20mmols/litre)

Plasmalyte 148 and Plasmalyte 148 + 5% glucose both contain 5mmols potassium per litre. Studies have shown that this amount of potassium is sufficient to maintain normal blood potassium levels in most patients. If extra potassium is needed only prescribe plasmalyte 148 and 15mmols KCl and make up as described below (this will in effect result in a solution that contains 20mmol potassium per litre).

Prescribing guidelines

To avoid error in prescription and making up of the fluids, the groups’ guidance would be that only two strengths of plasmalyte 148 with potassium should be prescribed:

  1. plasmalyte 148 (ie a plain bag of plasmalyte 148. This contains 5mmol/L of potassium)
  2. plasmalyte 148 (1L) + 15mmols KCl (this solution will contain a total of 20mmols/L of potassium)

For a plasmalyte 148 + 10% glucose, the prescription should state that 125mls 50% glucose be added to a 1L bag of plasmalyte 148 +5% glucose.

Samples of how the additives label be written are shown below.

How to make Plasmalyte 148 + 10% glucose

To a one litre (1L) bag of Plasmalyte 148 + 5% glucose, add 125mls of 50% glucose % (125 grams of glucose in 1125mL)

To ensure that the additive is fully mixed in to the fluid solution, please roll/shake/invert the bag a number of times

How to make Plamalyte 148 + 15mmols Potassium

To a one litre bag of Plasmalyte 148, add 15mmol KCl (ie 7.5mls 15%w/v potassium chloride solution)a

To ensure that the additive is fully mixed in to the fluid solution, please roll/shake/invert the bag a number of times.


  1. We acknowledge that the concentration of chloride in the final solution will be higher than 98mmols as shown on the plasmalyte bag. The prescription and drug label should read plasmalyte 148 and 15mmols KCl (see below)
Drug additive labels

Editorial Information

Last reviewed: 17 January 2024

Next review: 31 January 2024

Author(s): Dr A Shah & Dr G Bell

Version: 2