Published: 5 September 2019

Publications

Artemisia annua and QT interval prolongation

Prescriber Update 40(3): 51-52
September 2019

Introduction

Artemisia annua (also known as Qing hao, Sweet Annie or Sweet Wormwood) dried herb or extract are constituents in several natural health products available in New Zealand.

Artemisinin is a constituent of Artemisia annua, and its derivatives form the basis of the artemisinin-based combination therapies (ACTs) now recommended by WHO for treating certain types of malaria¹.

QT interval prolongation is associated with ACTs^2–4. Patients who use natural health products containing Artemisia annua may also be at increased risk of developing a prolonged QT interval. The risk is greater in patients taking other QT-prolonging medicines, or with other risk factors for long QT syndrome (LQTS).

Products containing Artemisia annua extract

Several products known to contain Artemisia annua extract have been prominently marketed in New Zealand. These products contain Artemisia annua herb or extract, either alone or in combination with other ingredients such as curcumin (turmeric)^5,6.

New Zealand does not have a register of herbal medicines or an approval system for natural health products so a complete list of products containing Artemisia annua dried herb or extract cannot be provided here.

Advise patients at risk of prolonged QT interval to carefully check the ingredients of any natural health product or dietary supplement before use. Patients taking QT-prolonging medicines or with other risk factors for LQTS should avoid taking products containing Artemisia annua.

Drug-induced QT interval prolongation

Drug-induced QT interval prolongation is discussed in a previous issue of Prescriber Update.

An up-to-date list of drugs that cause QT interval prolongation is available.

New Zealand case reports

The Centre for Adverse Reactions Monitoring (CARM) has received two reports of QT interval prolongation in individuals who were taking Arthrem (Artemisia annua extract in grapeseed oil): CARM ID numbers 122230 and 133141.

References

1. World Health Organization. 2015. Guidelines for the Treatment of Malaria (3rd edition). World Health Organization: Geneva. URL: www.who.int/malaria/publications/atoz/9789241549127/en/ (accessed 23 July 2019).
2. CredibleMeds. 2019. Combined list of drugs that prolong QT and/or cause torsades de pointes (TDP). URL: https://crediblemeds.org/index.php/new-drug-list (accessed 23 July 2019).
3. Funck-Brentano C, Ouologuem N, Duparc S, et al. 2019. Evaluation of the effects on the QT-interval of 4 artemisinin-based combination therapies with a correction-free and heart rate-free method. Scientific Reports 9(1): 883. DOI: 10.1038/s41598-018-37113-5 (accessed 23 July 2019).
4. World Health Organization. 2017. The cardiotoxicity of antimalarials. WHO Evidence Review Group Meeting, 13–14 October 2016, Varembe Conference Centre, Geneva, Switzerland. URL: www.who.int/malaria/mpac/mpac-mar2017-erg-cardiotoxicity-report-session2.pdf (accessed 23 July 2019).
5. Promisia. 2019. Arthrem. URL: http://arthrem.co.nz/Arthrem/Product (accessed 24 July 2019).
6. Good Health. 2019. Turmeric Extra Strength. URL: www.goodhealth.co.nz/products/detail/turmeric-extra-strength (accessed 24 July 2019).