The foundation of treatment for lead poisoning involves administration of a chelating agent (drug that binds lead in the blood and allows the lead to be removed from the body). Only one chelating agent is used at a given time and the choice of chelating agent depends on availability. However, lead must be removed from the intestinal tract before beginning treatment with chelating agents, because these medications can increase the absorption of lead from the intestinal tract into the blood stream and worsening of the dog's symptoms. Gastric lavage and enemas are used to remove lead objects from the stomach and intestinal tract. During gastric lavage, a large tube is passed through the mouth into the stomach. Water is pumped into the stomach and then drained, removing any stomach contents. This procedure requires sedation of the dog.
Surgery is indicated for removal of lead objects if they cannot be removed with gastric lavage and enemas.
Succimer is a chelator that is available in tablet form and is administered twice daily for 10 days. If the dog does not require hospitalization for his symptoms, the medication can be administered at home. Succimer can also be dissolved in water and administered rectally in unconscious patients.
Calcium EDTA is a chelator that is administered subcutaneously (under the skin) twice a day for five days during the time the patient is hospitalized. Calcium EDTA is not used in patients with pre-existing kidney disease and patients must receive fluids while they are on the drug. If blood lead levels remain high, Calcium EDTA treatment may need to be repeated beginning five days after the first treatment was finished. If the dog develops vomiting or diarrhea while on Calcium EDTA, your veterinarian may need to supplement zinc because Calcium EDTA chelates zinc as well as lead.
Penicillamine (Depen®, Cuprimine®) is a chelating agent that is given orally for long term use following Calcium EDTA therapy. Penicillamine is used primarily in patients with persistently elevated lead levels. This drug can be administered at home.
Placement of an intravenous catheter and administration of intravenous fluids is necessary for dogs that are dehydrated and for dogs that are receiving calcium EDTA.
Administration of anticonvulsants such as Diazepam (Valium®), Phenobarbital and pentobarbital may be necessary if the dog is having seizures. These drugs are usually only necessary during the period the dog is hospitalized and are rarely required long term.
Administration of Thiamine (Vitamin B1) complex may help reduce some of the symptoms of lead poisoning although the mechanism is unclear. Thiamine is not a chelating agent.
Optimal treatment for your dog requires a combination of home and professional veterinary care. Follow-up can be critical, especially if your dog does not improve rapidly.
Administer all prescribed medications as directed. Alert your veterinarian if you are experiencing problems treating your dog.
Prevent re-exposure to lead by removing the source responsible for the original intoxication.
Schedule an appointment with your veterinarian to recheck a blood lead level two weeks after therapy has been completed.