June 10, 2002: WHAT IS THE TOXICITY OF POKEWEED?

Pokeweed is a perennial that grows wild throughout the eastern half of the United States.  It has a green or red center stalk with oblong leaves.  The small berries grow in “grape-like clusters” and ripen from green to purple in the summer. The juices of the ripe berries leave a purple stain when handled which may attract young children. The entire plant is potentially toxic.  The root is the most toxic and the ripe berries the least toxic.  Potentially toxic doses are as little as 0.5 teaspoonful of the root and 10 or more of the berries.  The active components of pokeweed include phytolacca toxin (and related triterpene saponins) and mitogens.  The phytolacca toxin and other saponins can cause significant gastrointestinal irritation and produce a “foamy” diarrhea.  GI symptoms such as an oral burning sensation, vomiting, or diarrhea are the most common symptoms following pokeweed ingestion.  The vomiting and diarrhea may be significant enough to produce dehydration. Less commonly reported symptoms include headache, salivation, visual disturbances and possibly seizures, and are most likely actually resulting from untreated dehydration.  Symptoms following ingestion are self-limiting.

Many people cook pokeweed in the same way they cook other “greens” such as turnip greens.  This is common in rural areas of the south and it is referred to as “poke salad”, sometimes spelled “poke sallat”.  The leaves are boiled for 5 minutes, the water is discarded, fresh water is added, and the mixture is brought to a second boil.  This double boiling reportedly will destroy the toxin.  However, there are several reports of people developing gastrointestinal symptoms following this cooking method.  Cooked ripe pokeberries are considered edible and are sometimes used to make pies.  

As always, if there are any questions, call the MTPC.

I am interested in any questions that you would like answered in “Question of the Week.”  Please e-mail me with any suggestions at donna.seger@Vanderbilt.edu 

Donna Seger, M.D.
Medical Director
Middle Tennessee Poison Center