# Longitudinal study on the seasonal variation in methylphenidate consumption in the South African private healthcare sector

## TL;DR

This study shows that methylphenidate use in South Africa's private healthcare sector rose significantly over 11 years, with seasonal patterns linked to school calendars and a dip during the 2020 pandemic.

## Contribution

The study provides new insights into methylphenidate consumption trends and seasonal variations in South Africa, particularly during the pandemic.

## Key findings

- Methylphenidate consumption increased by 64.39% from 2013 to 2023.
- Consumption dropped in 2020 during the start of the COVID-19 pandemic.
- Seasonal peaks in consumption occurred before academic assessments in schools and universities.

## Abstract

A steady growth in the consumption of medicine for Attention-Deficit/Hyperactivity Disorder (ADHD) has been evident over the past two decades. The Coronavirus disease 2019 (COVID-19) pandemic is reported to have had an effect on stimulant consumption. Methylphenidate is the main active ingredient used in the treatment of ADHD, both in children and adults.

The primary aim was to analyze the consumption patterns of methylphenidate in the private healthcare sector in South Africa by means of a drug utilization study using the Defined Daily Dose (DDD) methodology to establish trends, detect seasonal variations and to compare the results with international studies.

A retrospective descriptive drug utilization study was conducted. IQVIA sales data from the South African private healthcare sector from 2013 to 2023 were analyzed. Consumption patterns were expressed as the number of Defined Daily Doses (DDDs)/1000 inhabitants/day and DDDs/1000 inhabitants/month. Ethical approval for the study was granted.

Methylphenidate consumption showed a steady increase in the years around the pandemic period, from 9.07 (in 2018) to 9.88 DDDs/1000 inhabitants/day (in 2023), with a notable lower consumption in 2020 when the COVID-19 pandemic started. Consumption in 2013 was only 6.01 DDD/1000 inhabitants/day, which indicates an increase of 64.39 % over the 11-year period. Seasonal peaks in consumption were observed in February, May, August and November, coinciding with times before assessment periods in schools and universities.

There was a clear visible upward trend in the consumption of methylphenidate, with a decrease during 2020, as was also observed in other countries. Similar studies are recommended for other central nervous system drug classes.

•Methylphenidate consumption increased by 64.39 % over 11 years (2013 to 2023).•Methylphenidate consumption decreased in 2020 during the COVID-19 pandemic.•Seasonal peaks and troughs in consumption coincided with academic school calendars.

Methylphenidate consumption increased by 64.39 % over 11 years (2013 to 2023).

Methylphenidate consumption decreased in 2020 during the COVID-19 pandemic.

Seasonal peaks and troughs in consumption coincided with academic school calendars.