Cardiovascular Warnings for Donepezil

The Therapeutic Goods Administration (TGA) advises that new cardiovascular warnings have been added to the product information and consumer medicine information documents for donepezil. These updates are based on post-market adverse event data that includes reports of atrioventricular block, QTc interval prolongation, and Torsades de Pointes.

Updates to the product information include warnings for the use of donepezil in patients with:

• QTc prolongation;
• A family history of QTc prolongation;
• Co-prescribed medicines that also cause QTc prolongation (e.g. amiodarone, sotalol, citalopram, phenothiazine derivatives);
• Certain heart problems (e.g. heart failure, recent heart attack, bradyarrhythmia); and
• Electrolyte disturbances (e.g. hypokalaemia and hypomagnesaemia).

Donepezil is a cholinesterase inhibitor used in the treatment of Alzheimer’s disease. This agent increases the concentration of acetylcholine, a neurotransmitter involved in memory processing and learning. However, acetylcholine also has inhibitory effects on the heart, which may be potentiated by donepezil.

Patients prescribed donepezil tend to be older and may be more likely to have pre-existing cardiovascular disease or be taking other medications. As the cardiovascular adverse effects associated with donepezil are potentially life-threatening, the TGA advises that monitoring may be required in at-risk patients.