Management overview for clonidine and guanfacine poisonings

Clonidine and guanfacine are centrally acting alpha₂-receptor agonists that cause sedation and bradycardia in poisoning. Effects are more pronounced in children and in people who do not take the medication regularly.

In clonidine poisoning, the onset of and peak sedation occurs within the first few hours after ingestion, and resolves earlier than bradycardia. Bradycardia is typically well tolerated, but persists for 24 to 48 hoursIsbister, 2017.

Guanfacine is available as a modified-release preparation. In guanfacine poisoning, the onset of symptoms is often delayed and symptoms may persist for many daysMishra, 2022.

Management of clonidine or guanfacine poisoning is focused on supportive care.