Potassium Iodide
Risk Factor: D
Class: Respiratory drugs
/ Expectorants
Contents of this page:
Fetal Risk Summary
The primary concern with the use of potassium iodide and the anti-infective iodine during pregnancy relates to the effect of iodide on the fetal thyroid gland. Because aqueous solutions of iodine are in equilibrium with the ionized form, all iodide or iodine products are considered as one group.
Iodide readily crosses the placenta to the fetus (1). When used for prolonged periods or close to term, iodide may cause hypothyroidism and goiter in the fetus and newborn. Short-term use, such as a 10-day preparation course for maternal thyroid surgery, does not carry this risk and is apparently safe (2,3). A 1983 review tabulated 49 cases of congenital iodide goiter dating back to 1940 (66 References) (4). In 14 cases, the goiter was large enough to cause tracheal compression resulting in death. Cardiomegaly was present in three surviving newborns and in one of the fatalities. In a majority of the cases, exposure to the iodide as a result of maternal asthma treatment.
Four studies have shown the potential hazard resulting from the use of povidone-iodine during pregnancy (5,6,7 and 8). In each case, significant absorption of iodine occurred in the mother and fetus following topical, vaginal, or perineal use before delivery. Transient hypothyroidism was demonstrated in some newborns (5,8).
Because a large number of prescription and over-the-counter medications contain iodide or iodine, pregnant patients should consult with their physician before using these products. The American Academy of Pediatrics considers the use of iodides as expectorants during pregnancy to be contraindicated (9).
Breast Feeding Summary
Iodide is concentrated in breast milk (4,10,11). In one report, a breast-feeding mother used povidone-iodine vaginal gel daily for 6 days without douching (10). Two days after stopping the gel, the mother noted an odor of iodine on the 7 1/2-month-old baby. The free iodide serum:milk ratio 1 day later was approximately 23:1. By day 7, the ratio had fallen to about 4:1 but then rose again on day 8 to 10:1. Serum and urine iodide levels in the infant were grossly elevated. No problems or alterations in thyroid tests were noted in the baby.
In a 2000 case report, a woman delivered a female infant at 29 weeks' gestation by cesarean section (11). An abscess of the abdominal wall 1 week after delivery was treated with IV antibiotics and iodine tampons (each tampon contained about 10.5 mg of iodine). Full breast-feeding of the infant was begun approximately 20 days after birth. At 29 days, neonatal hypothyroidism was diagnosed: thyroid-stimulating hormone (TSH) level 287.9 U/mL (normal range 0.4510.0 U/mL). Iodine levels in the mother's milk and infant urine were 4410 g/L (normal range 29490 g/L) and 3932 g/L (normal <185 g/L), respectively. At 32 days, iodine tampons and breast feeding were stopped and the infant was given levothyroxine (25 g/day). Six days later, thyroid function had normalized and breast feeding was restarted. The infant's thyroid function remained normal over a 4-month follow-up period (11).
Use of povidone-iodine immediately before delivery as a topical anesthetic for epidural anesthesia or cesarean section produced iodine overload in newborn infants who were breast-fed as evidenced by increased neonatal TSH concentrations (12). Breast-fed infants had a 25- to 30-fold increase in the recall rate at screening for congenital hypothyroidism (TSH >50 mU/L) compared with bottle-fed infants.
The normal iodine content of human milk has been recently assessed (13). Mean iodide levels in 37 lactating women were 178 g/L. This is approximately 4 times the recommended daily allowance (RDA) for infants. The RDA for iodine was based on the amount of iodine found in breast milk in earlier studies (13). The higher levels now are probably caused by dietary supplements of iodine (e.g., salt, bread, cow's milk). The significance to the nursing infant from the chronic ingestion of higher levels of iodine is not known. The American Academy of Pediatrics, although recognizing that the maternal use of iodides during lactation may affect the infant's thyroid activity by producing elevated iodine levels in breast milk, considers the agents to be compatible with breast feeding (14).
References
- Wolff J. Iodide goiter and the pharmacologic effects of excess iodide. Am J Med 1969;47:10124.
- Herbst AL, Selenkow HA. Hyperthyroidism during pregnancy. N Engl J Med 1965;273:62733.
- Selenkow HA, Herbst AL. Hyperthyroidism during pregnancy. N Engl J Med 1966;274:1656.
- Mehta PS, Mehta SJ, Vorherr H. Congenital iodide goiter and hypothyroidism: a review. Obstet Gynecol Surv 1983;38:23747.
- I'Allemand D, Gruters A, Heidemann P, Schurnbrand P. Iodine-induced alterations of thyroid function in newborn infants after prenatal and perinatal exposure to povidone iodine. J Pediatr 1983;102:9358.
- Bachrach LK, Burrow GN, Gare DJ. Maternal-fetal absorption of povidone-iodine. J Pediatr 1984;104:1589.
- Jacobson JM, Hankins GV, Young RL, Hauth JC. Changes in thyroid function and serum iodine levels after prepartum use of a povidone-iodine vaginal lubricant. J Reprod Med 1984;29:98100.
- Danziger Y, Pertzelan A, Mimouni M. Transient congenital hypothyroidism after topical iodine in pregnancy and lactation. Arch Dis Child 1987;62:2956.
- Committee on Drugs. American Academy of Pediatrics. Adverse reactions to iodide therapy of asthma and other pulmonary diseases. Pediatrics 1976;57:2724.
- Postellon DC, Aronow R. Iodine in mother's milk. JAMA 1982;247:463.
- Casteels K, Punt S, Bramswig J. Transient neonatal hypothyroidism during breastfeeding after post-natal maternal topical iodine treatment. Eur J Pediatr 2000;159:7167.
- Chanoine JP, Boulvain M, Bourdoux P, Pardou A, Van Thi HV, Ermans AM, Delange F. Increased recall rate at screening for congenital hypothyroidism in breast fed infants born to iodine overloaded mothers. Arch Dis Child 1988;63:120710.
- Gushurst CA, Mueller JA, Green JA, Sedor F. Breast milk iodide: reassessment in the 1980s. Pediatrics 1984;73:3547.
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Committee on Drugs, American Academy of Pediatrics. The transfer of drugs and other chemicals into human milk. Pediatrics 1994;93:13750.
Questions and Answers
Can potassium iodide be useful for nasa during space missions?, It has been said that potassium iodide can help to block harmful radiation. I take it about once or twice a week. It does have some great health benefits. In particular; it helps contribute to a healthy thyroid. But I have heard that this supplement has been recommended during a possible nuclear attack. So I would assume it could help block cosmic radiation as well, could it not?
The whole thing with taking iodine after a nuclear attack is to help prevent the body from absorbing radioactive iodine that's prevelant in fallout. It doesn't block radiation; it just prevents the body from retaining a particular radioactive isotope.
Since taking iodine doesn't block anything, it won't protect astronauts in space from cosmic radiation. Cosmic rays are emitted by the sun and are very high energy particles and waves that are very hard to stop.
What role does potassium iodide play in the generation of oxygen?How does this deffer from the role of sodie?, What role sies potassium iodide play in the gereration of oxygen?How does this deffer from the role of sodieum bicarbonate in the production of caron dixide?
Lancenigo di Villorba (TV), Italy
YOUR QUESTION IS NOT AN EASY ONE!!
I must examine the Thermodynamics and the Kinetic aspects of the reaction interested by your question.
THERMODYNAMICS
The former process interests an aqueous medium of potassium iodide (e.g. KI). As you noted, oxygen gas bubbles may lift up, how is it possible? I think you added some other chemical stuffs, e.g. hydrogen peroxide (H2O2). This chemical couple may react.
On the basis of the electrochemical fundaments, I start collecting the electrodic half-reactions, as follows :
i) 2 H+(aq) + 2e <---> H2(g) (0.00 V)
ii) I2(aq) + 2e <---> 2 I-(aq) (+0.55 V)
iii) O2(g) + 2 H+(aq) + 2e <---> H2O2(aq) (+0.68 V)
iv) HIO(aq) + H+(aq) + 2e <--->
<---> I-(aq) + H2O(aq) (+0.99 V)
v) O2(g) + 4 H+(aq) + 4e <---> 2 H2O(aq) (+1.22 V)
vi) 2 HIO(aq) + 2 H+(aq) + 2e <--->
<---> I2(aq) + 2 H2O(aq) (+1.49 V)
vii) H2O2(aq) + 2 H+(aq) + 2e <---> 2 H2O(aq) (+1.77 V)
Since I think you have NOT involved any "Electrical Energy Supplier" as Voltaic Battery, I compare the overwritten electrodic reactions in order to state what it happened. A well-known fundament of Electrochemistry states that the experiment runs when there are two or more half-reactions respecting some requests, the followings :
-) there will be a difference between the electrical potential GREATER THAN 0.15 V environ ;
-) the half-reaction having the GREATEST electrical potential value runs rightward, the half-reaction having the lowest potential runs leftward ;
-) since you noted oxygen bubbles, the experiment must runs leftward one of half-reaction involving O2(g) itself.
Thus, I state that the experiment mainly interst the II), III) and V) half-reactions...NOT only the latters, mainly themselves! Thus, I wait retrieve the following reactions :
2 KI(aq) + H2O2(aq) + 2 H+(aq) <--->
<---> I2(aq) + 2 H2O(aq) + 2 K+(aq) (Keq = 1E+70)
2 H2O2(aq) <---> 2 H2O(aq) + O2(g) (Keq = 1E+67)
Hence, oxygen bubbles may leaved by decomposition of hydrogen peroxide. Thermodynamics cannot delucidate the role of potassium iodide.
KINETIC
Some scientists stated the equilibrium involving iodine and several its compounds, e.g. iodide and hypoiodite. The latter takes part in a particular equilibrium shown by any aqueous solutions of iodine, as follows :
I2(aq) + H2O(aq) <---> HI(aq) + HIO(aq) (Keq = 1E-30)
Hydrogen peroxide increase the formation of hypoiodous acid and salts. A mechanism interpretating the kinetic data and the oxygen development may be the following :
step i) H2O2(aq) + I-(aq) + H+(aq) <----> HIO(aq) + H2O(aq)
step ii) HIO(aq) + H2O2(aq) <--->
<---> I-(aq) + H+(aq) + H2O(aq) + O2(g)
Starting from the electrical potential put in the overwritten collection table, I calculated that Keq is like 1E+26 for STEP I) while Keq is like 1E+10 for STEP II). The latter data are relatively great, but they closely refer to acidic media. In effect, weak acidity conditions fall down the phenomenon's rate, alkaline media stop it.
Nonetheless the latter data belong to thermodynamics informations, they verify the executability of the two steps.
CONCLUSIONS)
Thermodynamics and kinetic data verify the active role played by potassium iodide in decomposition of hydrogen peroxide when it is dissolved in ACIDIC MEDIA.
I hope this helps you.
What are the molecular weights for glucose, starch, and iodine potassium iodide?, I am writing a lab report, and I need to know the molecular weight of the following: glucose, starch, and iodine potassium iodide. I have to have sources. PLESE HELP!
Let me help you to go over it on your own!
To calculate the molecular weights you just need two things: first a periodic table & then what you are weighing!
Glucose: C6H12O6
Iodine: I2
potassium iodide : KI
notice that starch is a "polymer" and you can't calculate the molecular weight
An example: Iodine: I2 => I= 126.90
=> 126.90 * 2 = 253.80
find atomic masses in http://webelements.com
Do others yourself!
Good luck.
What does the reaction between sodium carbonate and potassium iodide form?, Sodium carbonate + Potassium Iodide -> ?
Could you please tell me what could be seen when the react.
Na2CO3 + 2 KI --> K2CO3 + Na+ + I-
if this reaction took place in alcohol, the K2CO3 would be visible as a white precipitant.
Does lead nitrate and potassium iodide precipitate when mixed?, My science teacher told us that silver and lead mostly always precipitates except in nitrate. Is this true?
So my question is if the reactants lead nitrate and potassium iodide were mixed would they preciptate? What about silver nitrate and iron chloride?
Please help!
1) It is true
2)
Pb(NO3)2 is soluble
KI is soluble
Pb(NO3)2 + 2 KI >> PbI2 (s) + 2 KNO3 (aq)
PbI2 will precipitate
the net ionic equation is :
Pb2+ (aq) + 2 I- (aq) >> PbI2 (s)
Which is better for radiation protection: Potassium Iodate or Potassium Iodide ?, I understand Potassium Iodide is a salt, and if unopened will still be Potassium Iodide in 50 years - and I know it works for this purpose, but I am wanting clarification if anyone can help.
The websites selling either product seems to be completely biased for their own products - please assist.
Thank You.
Off the top of my head, I can tell you that the purpose of using Potassium Iodide is to compete with radioactive iodine after a nuclear accident.
The thyroid gland naturally uptakes iodide ions for coversion into thyroid hormones, and cannot exclude radioactive iodide from this process. Therefore thyroid cancer is induced by the radioactive iodide.
I will have to check my source, but I have run accross a statement that if (after a nuclear accident) you paint one hand with iodide tincture, it will be slowly absorbed and serve the same purpose.
Too much iodide can affect the thyroid gland.
http://www.merck.com/mmpe/sec21/ch317/ch...
The link below tells the dose of KI.
http://www.merck.com/mmpe/sec01/ch005/ch...
The article mentions that sulfhydryl compounds are helpful in animals to survive radiation. Asparagus is loaded with suflhydryl compounds so having a few cans of that around might not be a bad idea.
Iodiate is an oxidizing agent, I cannot really see that as a good idea for the diet, but again I am talking off the top of my head.
What is the product of Zinc + hydrobromic acid and potassium iodide + bromine?, What is the net ionic equation for potassium iodide and bromine?
Zn + 2 HBr >> ZnBr2 + H2
2KI + Br2 >> 2KBr + I2
Can you describe in detail what happens when you mix potassium iodide and lead (II) nitrate?, So when you mix potassium iodide and lead (II) nitrate, I know it creates a yellow precipitate. But what's actually happening? Like, why does that happen?
KI(aq)+ Pb(NO3)2(aq)---->PbI2(s)+ KNO3(aq)
Notice the (aq), the reaction takes place only in solution where the ions are free to move and recombine.
PbI2 is an insoluble yellow compound which is used in making yellow oil paints. When the Pb++ and the I- ions combine they are taken out of solution as they precipitate.
