Potassium Iodide 99% 250g
Potassium Iodide is a chemical compound, medication, and dietary supplement. As a medication it is used to treat hyperthyroidism, in radiation emergencies, and to protect the thyroid gland when certain types of radiopharmaceuticals are used. In the third world it is also used to treat skin sporotrichosis and phycomycosis. As a supplement it is used in those who have low intake of iodine in the diet. It is administered orally.
Common side effects include vomiting, diarrhea, abdominal pain, rash, and swelling of the salivary glands. Other side effects include allergic reactions, headache, goitre, and depression. While use during pregnancy may harm the baby, its use is still recommended in radiation emergencies. Potassium iodide has the chemical formula KI. Commercially it is made by mixing potassium hydroxide with iodine.
Potassium iodide has been used medically since at least 1820. It is on the World Health Organization’s List of Essential Medicines. Potassium iodide is available as a generic medication and over the counter. Potassium iodide is also used for the iodization of salt.
Side effects
There is reason for caution with prescribing the ingestion of high doses of potassium iodide and iodate, as their unnecessary use can cause conditions such as the Jod-Basedow phenomena, trigger and/or worsen hyperthyroidism and hypothyroidism, and then cause temporary or even permanent thyroid conditions. It can also cause sialadenitis (an inflammation of the salivary gland), gastrointestinal disturbances, and rashes. Potassium iodide is also not recommended for people with dermatitis herpetiformis and hypocomplementemic vasculitis – conditions that are linked to a risk of iodine sensitivity.
There have been some reports of potassium iodide treatment causing swelling of the parotid gland (one of the three glands that secrete saliva), due to its stimulatory effects on saliva production.
A saturated solution of KI (SSKI) is typically given orally in adult doses several times a day (5 drops of SSKI assumed to be 1⁄3 mL) for thyroid blockade (to prevent the thyroid from excreting thyroid hormone) and occasionally this dose is also used, when iodide is used as an expectorant (the total dose is about one gram KI per day for an adult). The anti-radioiodine doses used for 131
I
uptake blockade are lower, and range downward from 100 mg a day for an adult, to less than this for children (see table). All of these doses should be compared with the far lower dose of iodine needed in normal nutrition, which is only 150 μg per day (150 micrograms, not milligrams).
At maximal doses, and sometimes at much lower doses, side effects of iodide used for medical reasons, in doses of 1000 times the normal nutritional need, may include: acne, loss of appetite, or upset stomach (especially during the first several days, as the body adjusts to the medication). More severe side effects that require notification of a physician are: fever, weakness, unusual tiredness, swelling in the neck or throat, mouth sores, skin rash, nausea, vomiting, stomach pains, irregular heartbeat, numbness or tingling of the hands or feet, or a metallic taste in the mouth.
In the event of a radioiodine release the ingestion of prophylaxis potassium iodide, if available, or even iodate, would rightly take precedence over perchlorate administration, and would be the first line of defence in protecting the population from a radioiodine release. However, in the event of a radioiodine release too massive and widespread to be controlled by the limited stock of iodide and iodate prophylaxis drugs, then the addition of perchlorate ions to the water supply, or distribution of perchlorate tablets would serve as a cheap, efficacious, second line of defense against carcinogenic radioiodine bioaccumulation.
The ingestion of goitrogen drugs is, much like potassium iodide also not without its dangers, such as hypothyroidism. In all these cases however, despite the risks, the prophylaxis benefits of intervention with iodide, iodate or perchlorate outweigh the serious cancer risk from radioiodine bioaccumulation in regions where radioiodine has sufficiently contaminated the environment.
Potassium iodide in its raw form is a mild irritant and should be handled with gloves. Chronic overexposure can have adverse effects on the thyroid. Potassium iodide is a possible teratogen.
Industrial uses
KI is used with silver nitrate to make silver iodide (AgI), an important chemical in film photography. KI is a component in some disinfectants and hair treatment chemicals. KI is also used as a fluorescence quenching agent in biomedical research, an application that takes advantage of collisional quenching of fluorescent substances by the iodide ion. However, for several fluorophores addition of KI in μM-mM concentrations results in increase of fluorescence intensity, and iodide acts as fluorescence enhancer.
Potassium iodide is a component in the electrolyte of dye sensitised solar cells (DSSC) along with iodine.
Potassium iodide finds its most important applications in organic synthesis mainly in the preparation of aryl iodides in the Sandmeyer reaction, starting from aryl amines. Aryl iodides are in turn used to attach aryl groups to other organics by nucleophilic substitution, with iodide ion as the leaving group.