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Potassium iodide (Oral)

Generic name: potassium iodide [ poe-TAS-ee-um-EYE-oh-dide ]
Brand names: Pima, SSKI, ThyroShield
Drug classes: Antithyroid agents, Expectorants

Medically reviewed by Drugs.com. Last updated on Aug 19, 2023.

Uses for potassium iodide

Potassium iodide is used to treat overactive thyroid and to protect the thyroid gland from the effects of radiation from inhaled or swallowed radioactive iodine. It may be used before and after administration of medicine containing radioactive iodine or after accidental exposure to radioactive iodine (for example, from nuclear power plant accidents that involved release of radioactivity to the environment). It may also be used for other problems as determined by your doctor.

Potassium iodide is taken by mouth. It may be taken as an oral solution, syrup, uncoated tablet, or enteric-coated delayed-release tablet. However, the delayed-release tablet form may cause serious side effects and its use is generally not recommended.

Some brands of the oral solution are available without a prescription.

Before using potassium iodide

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Potassium iodide may cause skin rash and thyroid problems in infants.

Geriatric

Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults. Although there is no specific information comparing use of potassium iodide in the elderly with use in other age groups, this medicine is not expected to cause different side effects or problems in older people than in younger adults.

Breast Feeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Interactions with Medicines

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

Proper use of potassium iodide

If potassium iodide upsets your stomach, take it after meals or with food or milk unless otherwise directed by your doctor. If stomach upset (nausea, vomiting, stomach pain, or diarrhea) continues, check with your doctor.

For patients taking this medicine for radiation exposure :

For patients taking the oral solution form of this medicine:

For patients taking the uncoated tablet form of this medicine:

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Precautions while using potassium iodide

Your doctor should check your progress at regular visits to make sure that this medicine does not cause unwanted effects.

For patients on a low-potassium diet:

Side Effects of potassium iodide

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

Less common

With long-term use

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Less common

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Commonly used brand name(s)

In the U.S.

Available Dosage Forms:

Therapeutic Class: Antithyroid Agent

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.