Evaluating the concept of a dilution bottle to increase the use of magnesium sulfate for the treatment of severe preeclampsia/eclampsia Final report

The dilution bottle contains 10mL of 50% magnesium sulfate solution and is marked with a fill line that indicates the fill volume at 25mL. This design allows for the direct withdrawal of 50% magnesium sulfate solution when required and the addition of sterile water to create a 20% magnesium sulfate solution. Technical feasibility assessments revealed that the bottle size must be a minimum of 75mL, including headspace, to avoid excess internal pressure. The materials used for the bottles presented some challenges, with Type I glass being common but potentially difficult to distribute due to its large size. Polyolefin polymers could alleviate this issue and are compatible with magnesium sulfate, but their use for bottle containers is somewhat unique and may result in higher costs. Commercial feasibility evaluations confirmed that listing the dilution bottle on national Essential Medicines Lists (NEMLs) is unlikely to present a significant hurdle. Most sub-Saharan African and South Asian countries already list 50% magnesium sulfate as an anticonvulsant, antiepileptic, or treatment for preeclampsia/eclampsia. However, producing a non-standard size bottle, such as the 75mL required for the dilution bottle, could have implications for production costs and time to market. User acceptability evaluations revealed that healthcare professionals do not appreciate or value the dilution bottle as much as expected. The process of diluting and withdrawing the correct amount was perceived to be complex and time-consuming, and healthcare professionals were concerned about product wastage and the potential for incorrect volumes to be withdrawn. Due to these issues, PATH recommends termination of any further development of the dilution bottle. Despite the findings and conclusions about the dilution bottle, healthcare professionals expressed a preference for having a 20% magnesium sulfate solution, which would obviate potential mistakes in dilution and facilitate timely treatment of women with preeclampsia/eclampsia. However, a 20% concentration of magnesium sulfate is rarely listed on NEMLs, and changing these lists to include a 20% magnesium sulfate solution would require substantial time and effort. Additionally, incentivizing manufacturers to produce and supply a 20% magnesium sulfate solution would be difficult due to the relatively small market size for this critical medicine.