Management overview for chlorophenoxy herbicide poisoning

Note: Urgently contact a clinical toxicologist or poisons information centre if chlorophenoxy herbicide poisoning is suspected.

Chlorophenoxy herbicides cause dose-dependent uncoupling of oxidative phosphorylation and subsequent multiorgan failure. They include:

2,4-D (2,4-dichlorophenoxyacetic acid)
MCPA (2-methyl-4-chlorophenoxyacetic acid)
mecoprop (methylchlorophenoxypropionic acid)
dichlorprop (dichlorophenoxypropanoic acid).

Chlorophenoxy herbicides are often coformulated with other herbicides, some of which are more toxic than chlorophenoxy herbicides (eg bromoxynil; see also Herbicide poisonings). All chlorophenoxy herbicides preparations also contain other ingredients, such as solvents and surfactants, that can contribute to toxicity.

If chlorophenoxy herbicide poisoning is suspected, particularly involving deliberate ingestions, urgently contact a clinical toxicologist or poisons information centre (13 11 26). The mainstay of management is supportive care. Severe poisoning is only likely after deliberate ingestion, and treatment may involve enhanced elimination techniques.