Page 2108 - Cote clinical veterinary advisor dogs and cats 4th

1051.e4 Zinc Oxide Toxicosis

Zinc Oxide Toxicosis
VetBooks.ir

diagnostic. There are no confirmatory laboratory
BASIC INFORMATION
tests available. PROGNOSIS & OUTCOME
Definition • Expect rapid and complete recovery within
Acute vomiting, lethargy, anorexia, and diarrhea Differential Diagnosis 24 hours.
follow the ingestion of concentrated (10%-40%) • Dietary indiscretion/indigestion • Ingestion is not expected to result in systemic
zinc oxide–containing products such as diaper • Pancreatitis zinc toxicosis because most dogs rapidly
rash ointments, creams, hemorrhoid prepara- • Parvoviral enteritis vomit and self-decontaminate.
tions, calamine lotion, and some sunblocks. • GI obstruction
• Other causes of acute vomiting (p. 1293) PEARLS & CONSIDERATIONS
Synonyms • Differentiation: vomit often looks like the
Zinc oxide: Chinese white, zinc white, ZnO product (white, thick, greasy). Comments
• Acute ingestion of zinc oxide–containing
Epidemiology Initial Database ointments is not likely to result in systemic
SPECIES, AGE, SEX • If zinc oxide ingestion is known, diagnostic zinc toxicosis. Unlike solid metallic zinc–con-
All animals are susceptible; dogs are most testing is not required. taining objects, which tend to remain in the
commonly affected. • If vomiting is significant and dehydration is GI tract for an extended period, ointments/
present, a packed cell volume/total protein creams are rapidly eliminated.
RISK FACTORS (PCV/TP) assay and electrolyte panel may • Rarely, repeated use of concentrated zinc
Young, unsupervised pets are most likely to be appropriate. oxide products may result in systemic zinc
ingest products containing zinc oxide. • If ingestion is not known, tests may be toxicosis. Zinc toxicosis has been reported
appropriate to rule out other causes of in a dog when 40% zinc oxide ointment
Clinical Presentation acute onset vomiting (e.g., GI obstruction, was applied dermally for 4 days and the dog
HISTORY, CHIEF COMPLAINT parvovirus). licked off most of the ointment after each
• History of exposure to zinc oxide–containing application.
ointment TREATMENT • Additional ingredients such as cod liver oil
• Acute onset of vomiting, occasionally with make the products attractive to dogs.
blood Treatment Overview
• Vomit may look like the product (white, Withhold food and water. Control vomiting, Prevention
thick, greasy) and maintain hydration as needed. Treatment Keep all ointments/creams containing zinc oxide
• Acute allergic reaction of acute allergic reaction may be needed. out of the reach of pets.
PHYSICAL EXAM FINDINGS Acute General Treatment Technician Tips
• Commonly see vomiting, lethargy, nausea, • Activated charcoal does not bind zinc oxide Prevention of licking (with use of an Elizabethan
and diarrhea and increases the risk of aspiration. collar) reduces the risk of systemic toxicosis
• Some dogs have an allergic reaction and • Nothing by mouth (NPO) until 2 hours when zinc oxide creams are applied to dog’s
present with urticaria and angioedema. after last episode of vomiting skin.
• Consider antiemetics such as maropitant
Etiology and Pathophysiology 1 mg/kg SQ q 24h in dogs and cats if SUGGESTED READING
• Zinc oxide–containing ointments or creams vomiting is severe and GI tract obstruction National Library of Medicine, Medline Plus: Zinc
are used as topical skin protectants, astrin- (due to ingestion of the container) has been oxide overdose [human toxicology summary]
gents, and bactericidal agents. ruled out. (website). http://www.nlm.nih.gov/medlineplus/
• Most products contain 10%-40% zinc oxide. • Most cases do not require IV fluid therapy ency/article/002571.htm.
• Ointments may also contain vitamin A or because clinical signs resolve within 12 hours.
D, local anesthetics (benzocaine), cod liver • Allergic reactions may persist longer (24 ADDITIONAL SUGGESTED
oil, beeswax, petrolatum, or mineral oil. hours). READINGS
• Zinc salts are irritating to the gastrointestinal ○ For allergic reaction: diphenhydramine Welch SL: Oral toxicity of topical preparations. Vet
(GI) mucosa. (dogs, cats) 2 mg/kg PO, SQ, or IM q Clin North Am Small Anim Pract 32:443-453,
• Vomiting is acute and can be profound but 8-12h) 2002.
ultimately is self-limited. • Further information on treatment of acute
• Some dogs show an allergic reaction (urti- allergic reactions is provided on p. 54. AUTHOR: Karla Smith, DVM
EDITOR: Tina Wismer, DVM, MS, DABVT, DABT
caria, angioedema). This is believed to be
due to carriers in the product. Possible Complications
GI foreign body if the container was ingested
DIAGNOSIS
Diagnostic Overview
Evidence of exposure to zinc oxide–contain-
ing product and self-limited gastritis can be

www.ExpertConsult.com