Elephant specific information, if available, is in blue.

Chemistry – Sodium iodide occurs as colorless, odorless crystals or white crystalline powder. It will develop a brown tint upon degradation. Approximately 1 gram is soluble in 0.6 ml of water and 2 ml of alcohol.

Storage/Stability/Compatibility – Commercially available veterinary injectable products should generally be stored at room temperature (15- 30° C). Sodium iodide injection is re­portedly incompatible with vitamins B & C injection.

Pharmacology – While the exact mode of action for its efficacy in treating actinobacillosis is unknown, iodides probably have some effect on the granulomatous inflammatory pro­cess. Iodides have little, if any in vitro antibiotic activity.

Uses/Indications – The primary use for sodium iodide is in the treatment of actinobacillosis and actinomycosis in cattle. It has been used as an expectorant with little success in a variety of species and occasionally as a supplement for iodine deficiency disorders. In horses, oral sodium iodide has been the classical treatment for sporotrichosis.

Pharmacokinetics – Little published information appears to be available. Therapeutic efficacy of intravenous sodium iodide for actinobacillosis is rapid, with beneficial effects usually seen within 48 hours of therapy.

Contraindications/Precautions/Reproductive Safety – Sodium iodide injection labels state that it should not be given to lactating animals or to animals with hyperthyroidism. Do not inject intramuscularly (IM).

Iodides should be given slowly intravenously and with caution to horses as severe generalized reactions have been reported.

Anecdotal reports that iodides can cause abortion in cattle persist and label information of some veterinary products state not to use in pregnant animals. Clearly, potential risks versus benefits of therapy must be weighed.

Adverse Effects/Warnings – In ruminants, the adverse effect profile is related to excessive iodine (see Overdosage below). Young animals may be more susceptible to iodism than adults. Foals have developed goiter when mares have been excessively supplemented.

Overdosage – Excessive iodine in animals can cause excessive tearing, nasal discharge, scaly haircoats/dandruff, hyperthermia, decreased milk production and weight gain, coughing, inappetence and diarrhea.

Drug Interactions – Iodides may enhance the efficacy of thyroid medications and may decrease the efficacy of antithyroid medications.

Doses –

Horses:

For treatment of sporotrichosis:

a) Sodium iodide 20 – 40 mg/kg orally daily for several weeks (Fadok 1992)

Monitoring Parameters/Client Information – Ruminants: 1) Clinical efficacy 2) Signs of iodism (excessive tearing, nasal discharge, scaly haircoats/dandruff, hyperthermia, de­creased milk production and weight gain, coughing, inappetence, and diarrhea). Although formal withholding times were not located, there is concern about using this product in animals about to be slaughtered. In the interest of public health, author recommends not using within 30 days of slaughter.

Dosage Forms/Preparations/FDA Approval Status –

Veterinary-Approved Products:

Sodium Iodide Injection 20 g/100 ml (20%; 200 mg/ml) in 250 ml vials—available as multi- or single use vials; Generic; (Rx)

Human-Approved Products: NOTE: The following are listed for information purposes.

The above monograph pertains to the veterinary injectable product only.

Sodium Iodide123 Oral Capsules 3.7 mBq and 7.4 mBq (Note: Radioactive isotope used for thyroid diagnostic procedures) (Mallinckrodt); (Rx)

Sodium Iodide131 Capsules and Oral solution (Note: Radioactive isotope used for treatment of hyperthyroidism and thyroid carcinoma; requires NRC approval for use); (Bracco, Mallinckrodt); (Rx)