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Lugol's Side Effects

Generic Name: iodine / potassium iodide

Note: This document contains side effect information about iodine / potassium iodide. Some of the dosage forms listed on this page may not apply to the brand name Lugol's.

Applies to iodine / potassium iodide: oral solution

Along with its needed effects, iodine/potassium iodide 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 while taking iodine / potassium iodide:

Less common
  • Hives
  • joint pain
  • swelling of the arms, face, legs, lips, tongue, and/or throat
  • swelling of the lymph glands
With long-term use
  • Burning of mouth or throat
  • confusion
  • headache (severe)
  • increased watering of mouth
  • irregular heartbeat
  • metallic taste
  • numbness, tingling, pain, or weakness in hands or feet
  • soreness of teeth and gums
  • stomach upset
  • symptoms of head cold
  • unusual tiredness
  • weakness or heaviness of legs

Some side effects of iodine / potassium iodide 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

Some side effects of Lugol's may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

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