are larkspur flowers poisonous
Larkspur Toxicity. Larkspurs tend to become less toxic as they mature, according to the ASPCA. The alkaloids in these plants cause neuromuscular blocking because they inhibit a neurotransmitter called acetylcholine. You may see drooling, vomiting or constipation after your dog has eaten larkspurs.arkspurs (Delphinium species) have the potential to be highly toxic to dogs, although pets generally donât eat them. These flowering plants contain diterpene alkaloids, which can cause health concerns ranging from vomiting to death.