How many sachets of ORS should an ORS/Zinc co-pack contain and what size should they be?

GRZ co-pack with contents

This discussion is based on ColaLife’s field experience in Zambia during the Kit Yamoyo trial (2012-13) and subsequent scale-up (2014-2018) as well as informal discussions with colleagues working in this area and common sense. There is a dearth of research on this specific topic, although it is possible to extrapolate from the scant literature that has been published, as referenced below.


Our conclusions are:

  • One litre ORS sachets should NOT be used in ORS/Zinc co-packs, as is current practice.
  • If 500 mL ORS sachets are used, then four should be provided in a co-pack.
  • If 200 mL ORS sachets are used, then between four and six should be provided in a co-pack.
  • 200 mL sachets are preferred over 500 mL sachets as they equate to a ‘cup full’ of solution. Vessels to measure 500 mL are less easily available in low resource settings than cups or glasses.
  • A measuring feature incorporated into the co-pack packaging is highly desirable.[1]

Please read on for the detail behind these conclusions.


ORS sachet size

One litre ORS sachets

With the emphasis in recent years on Integrated Community Case Management (iCCM) more and more children are treated in the home for diarrhoea. One litre sachets were not designed for home settings. They were designed for use in health facilities, at a time when the recommendation was that caregivers should make their own sugar/salt solution to treat diarrhoea in the home. In a health facility, where a number of children may have diarrhoea and where it is likely that the means and skill to measure one litre of safe water correctly are present, it makes sense to mix ORS in batches of one litre. However, in low resource settings, the home situation is very different:

  1. A caregiver will generally be dealing with only one diarrhoea case at a time.
  2. The caregiver may not know what a litre is or have the knowledge to measure it correctly.[2, 3, 4]
  3. Caregivers may not have the means to measure a litre of water accurately.[1, 2]
  4. Safe water is a precious commodity; bringing water to the home and making is safe takes time and resources.[2]
  5. Caregivers may be reluctant to make up a full litre of ORS as this is more than a child will drink in 24 hours[1, 2, 3]. Any solution remaining after 24 hours should be thrown away due to the risk of contamination and caregivers are reported to see this as a waste of medicine (ORS) and a waste of safe water.[2, 4]

Furthermore, if a co-pack provides two 1 L sachets, and the caregiver follows the instructions (ie uses the whole sachet in a litre of safe water and throws away unused solution after 24 hours) then two 1 L sachets only provide treatment for two days. This is unlikely to be enough time to cover the length of a diarrhoea episode, which may last 4 days or 8 in severe cases [4, 5].

Despite these serious issues, 1 L sachets are the most common size used in current ORS/Zinc co-packs. This needs to change for the reasons outlined above and below.


500 mL ORS sachets

Because of the inappropriateness of 1 L sachets for the treatment of diarrhoea in the home, an increasing number of ORS/Zinc co-packs are being manufactured with four 500 mL ORS sachets. This is a big improvement over 1 L sachets for the reasons outlined above. Assuming a child drinks around 400 mL of ORS a day,[6] this will allow treatment for four days with a reduced risk of contamination of the ORS solution.

A disadvantage of this sachet size is that it requires the caregiver to know what 500 mL is and to have a vessel that measures 500 mL. Vessels that measure 500 mL are not common in poor households.


200 mL ORS sachets

Flexi-pack measuring in black handAmong the few studies available, the 200mL sachet size has been a stated preference of caregivers[4] and has been seen as a useful innovation.[2, 9] This size was well received in ColaLife’s work in Zambia by caregivers and health staff and has been consistently procured in co-pack format by the Zambian government since 2018.  In addition to addressing points 1-5 above, a 200 mL sachet makes a cup-full of ORS solution; this further reduces the risk of contamination and inaccurate measuring. Cups are generally available even in the poorest of households which makes measuring the correct amount of water less of a challenge. The co-pack produced for the government in Zambia (pictured above) has a 200 mL measuring functionality built into the packaging (picture to the right).


Number of ORS sachets to include in a co-pack

When moving from two 1 L sachets – which make up a total of two litres of ORS solution – to smaller sachets, there appears to be a tendency to focus the overall quantity of ORS provided by the co-pack rather than the duration of the treatment they provide. So, the tendency currently is to supply four 500 mL sachets and ten 200 mL sachets.

While four 500 mL sachets does seem appropriate, ten 200 mL sachets seems excessive.

In our trial in Zambia,[7, 8, 9] eight 200 mL sachets were provided in the prototype co-pack. At the endline caregivers were asked how many sachets they actually used. The responses are summarised in the graph below.

Number of ORS sachets used (average over both districts)

At the time we interpreted this data as follows:[7]

  • Only 10% said they used all eight sachets and these were also outliers. We concluded that these caregivers either used all eight sachets because there were eight supplied in the co-pack or that they said they used eight as they thought that was the expected answer.
  • 75% of caregivers said they used four sachets or fewer.

In addition, our work in Zambia gave further insights:

  • The average duration of treatment among caregivers at baseline (receiving two 1L sachets of ORS) was 2.75 days.[7]
  • We calculated how long caregivers treated children among the cohort who used only four 200 mL sachets or fewer; this was 2.78 days.
  • Affordability was crucial.[10]

The outcome was that the scale-up version of the co-pack in Zambia contains four sachets. This has been the case since they were first produced in 2015.

In 2018, three years into the scale-up, co-pack users were surveyed again and a handful of respondents said they would have liked more than four 200 mL sachets.

Based on this experience and subject to affordability considerations, we believe that six 200 mL ORS sachets would be optimal to include in an ORS/Zinc co-pack.



[1] A picture is worth a 1000 words: visualizing the challenges of effective diarrhoea treatment
[2] Greenland, K., Chipungu, J., Chilengi, R. et al. Theory-based formative research on oral rehydration salts and zinc use in Lusaka, Zambia. BMC Public Health 16, 312 (2016).
[3] Touchette PE, Elder J, Nagiel M. (1990) How much oral rehydration solution is actually administered during home-based therapy? J Trop Med Hyg. 1990 Feb;93(1):28-34.
[4] Zwisler G, Simpson E, Moodley M. Treatment of diarrhea in young children: results from surveys on the perception and use of oral rehydration solutions, antibiotics, and other therapies in India and Kenya. J Glob Health 2013;3(1):010403. doi: 10.7189/jogh.03.010403 [published Online First: 2013/07/05]
[5] Lamberti, L.M., Fischer Walker, C.L. & Black, R.E. Systematic review of diarrhea duration and severity in children and adults in low- and middle-income countries. BMC Public Health 12, 276 (2012).
[6] Dr Olivier Fontaine (personal communication)
[7] ColaLife Operational Trial Zambia Endline Survey Report, Ruralnet Associates, 2014.
[8]  Ramchandani R, Berry S, Berry J, et al Emulating value-chains of fast-moving consumer goods to improve uptake of co-packaged ORS and zinc for childhood diarrhoea: evaluation of the ColaLife trial BMJ Innovations Published Online First: 06 June 2022. doi: 10.1136/bmjinnov-2021-000914
[9] Design thinking to improve rational use of Oral Rehydration Salts: Lessons from an innovative co-packaged diarrhoea treatment kit. Ramchandani R, Berry S, Berry J, Pratt B A, Saka A, Black R E (submitted for publication)
[10] IDInsight Mapping the kit Yamoyo demand curve2013. Available: