potassium iodide

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Pronunciation: poe TAH see um EYE oh dide

Brand: iOSAT, ThyroSafe, ThyroShield

What is the most important information I should know about potassium iodide?

Potassium iodide is used to thin mucus and loosen congestion in people with chronic breathing problems that can be complicated by thick mucus in the respiratory tract.

Potassium iodide can cause thyroid problems, high potassium levels in your blood, or iodide poisoning. Call your doctor at once if you have swelling in your neck or throat, chest pain, irregular heart rate, muscle weakness, tingly feeling, pain or burning in your mouth, severe headache, or eye irritation.

What is potassium iodide?

Potassium iodide is the potassium salt form of iodide, a naturally occurring substance.

Potassium iodide can be used as an expectorant to thin mucus and loosen congestion in your chest and throat.

Potassium iodide is used in people with chronic breathing problems that can be complicated by thick mucus in the respiratory tract, such as asthma, chronic bronchitis, or emphysema.

Potassium iodide may also be used for purposes not listed in this medication guide.

What should I discuss with my healthcare provider before taking potassium iodide?

You should not use this medication if you have a history of previous allergic reaction to iodide, iodine, or other medicines.

To make sure potassium iodide is safe for you, tell your doctor if you have:

  • kidney disease;
  • high levels of potassium (hyperkalemia) in your blood;
  • Addison's disease (an adrenal gland disorder);
  • tuberculosis;
  • a thyroid disorder;
  • heart disease; or
  • a genetic muscle disorder.

FDA pregnancy category D. Do not use potassium iodide if you are pregnant. It could harm the unborn baby. Use effective birth control, and tell your doctor if you become pregnant during treatment.

Potassium iodide can pass into breast milk and may harm a nursing baby. You should not breast-feed while using this medicine.

How should I take potassium iodide?

Potassium iodide is usually taken 3 to 4 times per day. Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.

Measure liquid medicine with the special dose-measuring dropper provided with your medication. If you do not have a dose-measuring device, ask your pharmacist for one.

Mix this medicine with a full glass of milk, water, or fruit juice.

Take with food or milk to avoid an upset stomach.

Use this medicine for only as long as needed to get the best results. Your doctor can determine how long to treat you with potassium iodide.

This medication can cause unusual results with certain medical tests. Tell any doctor who treats you that you are using potassium iodide.

Store at room temperature away from moisture, heat, and light. Keep the bottle tightly closed when not in use. Avoid storing the medicine in very cold temperatures. If the medicine changes color to brown or yellow, throw it away and call your pharmacist for new medicine.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking potassium iodide?

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

What are the possible side effects of potassium iodide?

Get emergency medical help if you have any of these signs of an allergic reaction: hives, itching, severe tingling; fever, swollen glands, joint pain; difficult breathing; swelling of your face, lips, tongue, or throat.

Stop using this medicine and call your doctor at once if you have:

  • swelling in your neck or throat (enlarged thyroid);
  • chest pain, rapid or irregular heart rate, feeling anxious or irritable;
  • severe headache, metallic taste in your mouth;
  • puffy eyelids, irritated eyes, acne or severe skin rash;
  • pain or burning in your mouth or throat, increased salivation;
  • fever, cold symptoms (stuffy nose, sneezing, sore throat);
  • high potassium (slow heart rate, weak pulse, muscle weakness, tingly feeling).

Common side effects may include:

  • swollen glands in your lower jaw;
  • nausea, vomiting, diarrhea, upset stomach, or stomach pain;
  • confusion, tired feeling, numbness;
  • mild skin rash; or
  • weakness or heavy feeling in your hands or feet.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect potassium iodide?

Tell your doctor about all medicines you use, and those you start or stop using during your treatment with potassium iodide, especially:

  • lithium;
  • an ACE inhibitor--benazepril, captopril, enalapril, fosinopril, lisinopril, moexipril, perindopril, quinapril, ramipril, or trandolapril;
  • a diuretic or "water pill"--amiloride, spironolactone triamterene;
  • medications to treat overactive thyroid--methimazole, propylthiouracil (PTU), radioactive iodine; or
  • multivitamin or mineral supplements that contain potassium.

This list is not complete. Other drugs may interact with potassium iodide, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Where can I get more information?

Your pharmacist can provide more information about potassium iodide.


Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

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