Astragalus spp.

Commonname(s) Crazyweed, emory milk vetch, locoweed, milk vetch, poison vetch, red-stemmed peavine, Texas loco, timber milk vetch, woolly locoweed. (See also Oxytropis spp.)

Toxin(s) several alkaloids, methemoglobin formation.

Toxic part(S) Leaves.

Signs Poisoning of dogs and cats would be unlikely with this plant. It has been known to cause serious loss in cattle, sheep, and other range animals. Humans have also been reported to have been poisoned. Signs reported in humans are related to selenium accumulation. Reported signs include pallor, garlicky odor on the breath, gastrointestinal disturbances, nausea, vomiting, tightness in the chest, drowsiness, and brain damage.

Treatment Treatment is supportive and symptomatic. If methemoglobinemia is detected, it is treated as follows:

1. Ascorbic acid 20 to 30 mg/kg PO or 20 mg/kg IV slowly
2. Methylene blue

Dogs    3 to 4 mg/kg IV slowly if ascorbic acid has not been
             of benefit.

Cats    1.5 mg/kg has been reported to be beneficial to cats with nitrite-induced methemoglobinemia. Given in the absence of               methemoglobinemia, methylene blue may cause Heinz body formation.