Details About Overdose or Poisoning Generic Salt :: Iodide, Potassium Iodide, KI
Iodide (Potassium Iodide, KI)
Drug Pharmacology ::
I. Pharmacology. Iodine-131is a product of fission reactions and is likely to be a major form ofinternal radioactive contamination after a major nuclear reactoraccident or weapon detonation. Potassium iodide (KI) blocks thyroidgland uptake of the radioactive isotopes of iodine (to prevent thyroidcancer) by both diluting the radioactive iodine and “filling” the glandwith nontoxic iodine. For optimal protection, KI should be administeredbefore or at the time of exposure to inhaled radioactive iodines butwill have protective effects if initiated up to 3 or 4 hours afterexposure. If the exposure to radioactive iodines persists, dailyadministration is indicated.
Drug Indications ::
Indications. Potassiumiodide is indicated for prevention of uptake of radioactive isotopes ofiodine by the thyroid gland; therefore, when a public health emergencyhas occurred in which sufficient exposure to radioactive iodine islikely, potassium iodide is indicated. Note: KI should be used only when and if directed by federal, state, or local public health officials.
Drug Contra-Indications ::
III. Contraindications./b>
Knowniodine allergy. Persons with the rare disorder of dermatitisherpetiformis and hypocomplementemic vasculitis are at increased riskof sensitivity.
Iodine may be used in pregnancy and in infants and children, but safety has not been established clearly (see IV, below).
Drug Adverse Effects ::
IV. Adverse effects
GIupset, diarrhea, burning of throat, metallic taste in mouth, and,rarely, sialoadenitis (inflammation of the salivary glands). Theseeffects become more common as duration of therapy and dosing increase.
Allergicreactions ranging from skin rashes to respiratory distress may occur,though life-threatening reactions are very uncommon.
Iodine-inducedthyrotoxicosis, hypothyroidism, and goiter may occur, but incidence isprobably less than 2% even if therapy is used for a longer duration.
A bluish skin discoloration involving sweat glands may occur after large doses of iodine-containing products.
E. Use in pregnancy. FDAcategory D (see Table III–1). Crosses the placental barrier and maycause hypothyroidism and goiter in the fetus. Risk is minimal withshort-term use (eg, 10 days) and when given long periods before term.
F. Use in Neonates. Because of the increased risk of hypothyroidism in neonates (< 1 month old), thyroid function tests should be monitored.
Drug Lab Interactions ::
Drug or laboratory interactions
Synergistic hypothyroid activity with lithium.
TSH and free T4monitoring of thyroid function is reliable in the setting of standarddosing of potassium iodide. Recommended in all neonates treated with KI.
Riskof hyperkalemia with prolonged use along with other potassiumsupplements and potassium-sparing medications (eg, spironolactone).However, the daily dose of potassium from KI is only about 3–4 mEq.
Drug Dose Management ::
Dosage and method of administration
Thereare various dosing guidelines, including those recommended by the USFood and Drug Administration and the World Health Organization (WHO).Public health officials should decide on the regimen they will use in aspecific situation. See http://www.fda.gov/cder/guidance/5386fnl.htmfor a guidance document from the FDA’s Center for Drug Evaluation andResearch.
Generallyfor adults > 18 years, 130 mg orally every day is recommended. Oraldaily doses for other ages: adolescents and children (from 3–18 years),65 mg; 1 month–3 years, 32 mg; 0–1 month, 16 mg. Children who are adultsize (approaching 150 pounds) should be given an adult dose of 130 mg.
C. Duration of therapy may be from 1 day to many weeks, depending on public health recommendations.
Drug Chemical Formulations ::
Formulations
Oral (Thyro-Block,others). Scored tablets (130 mg and 65 mg) of potassium iodide.Formulations of potassium iodide syrups (325 mg KI/5 mL) and oralsolutions such as Lugol’s solution (5% iodine and 10% KI) may be found.
Potassiumiodide solution can be made from crushed KI tablets for use in childrenand adults unable to swallow tablets. Prepare with a 130-mg tablet (ortwo 65-mg tablets) crushed and mixed with 4 teaspoons (20 mL) of wateruntil dissolved, then 4 teaspoons (20 mL) of chocolate milk, orangejuice, soda, or baby formula. This results in a 130 mg per 8teaspoonfuls (40 mL) solution. Plain water or low-fat milk may notadequately mask the salty, unpleasant taste of KI tablets. The solutionwill keep up to 7 days in the refrigerator. The FDA recommends that thesolution be prepared weekly and the unused portion discarded.(Reference: FDA’s Center for Drug Evaluation and Research HomePreparation Procedure for Emergency Administration of Potassium IodideTablets to Infants and Small Children:http://www.fda.gov/cder/drugprepare/kiprep.htm).
C. The suggested minimum stocking level to treat a 70-kg adult for the first 24 hours is one 130-mg tablet.
