Ivermectin dose assessment without weighing scales

Area of Science:

• Public Health
• Tropical Medicine
• Pharmacology

Background:

• Mass chemotherapy campaigns for onchocerciasis rely on accurate ivermectin dosing.
• Weighing patients is a common method but can be impractical in large-scale field operations.
• Alternative methods for ivermectin dose assessment are needed to improve efficiency and accessibility.

Purpose of the Study:

• To evaluate two alternative methods for assessing ivermectin dosage in mass chemotherapy campaigns.
• To compare the accuracy and practicality of height-based and visual estimation methods against traditional weighing.
• To determine the potential for these methods to optimize ivermectin distribution in onchocerciasis control programs.

Main Methods:

• A height-based dosing categorization system was developed and tested.
• A visual appearance-based estimation method was assessed by multiple observers.
• Data were collected from participants in a placebo-controlled ivermectin trial in Nigeria.

Main Results:

• The height-based method resulted in 0.5% underdosed, 46.5% correctly dosed, 51.7% overdosed by 1/2 tablet, and 1.2% overdosed by 1 tablet.
• The visual appearance method achieved 82% correct dosing estimates, with all incorrect estimates deviating by only 1/2 tablet.
• Both methods demonstrated potential for practical application in mass drug administration.

Conclusions:

• Height and visual appearance are viable alternatives to weighing for ivermectin dosing in onchocerciasis control.
• These simplified dosing strategies can enhance the efficiency and effectiveness of mass chemotherapy campaigns.
• Further implementation studies are warranted to confirm the real-world applicability of these methods.