Despite having similar-sounding names, povidone iodine and potassium iodide differ in terms of use. Both substances contain iodine, but povidone iodine is an antiseptic solution used in disinfecting wounds and potassium iodide is a medication used in conditions like radiation exposure. Always use both substances as indicated by your doctor in order to avoid potential adverse reactions.
Uses
Potassium iodide helps thin mucus secretions in your respiratory tract caused by asthma, bronchitis and emphysema, and it is used in treating hyperthyroidism and cutaneous sporotrichosis. Potassium iodide also protects your thyroid gland from radiation, as explained by MerckManuals.com. In contrast, povidone iodine is used as an antibacterial disinfectant in treating minor wounds. Povidone iodine is designed for external use only. Unlike potassium iodide, povidone iodine is not meant to be ingested.
Dose
Povidone iodine is administered as a topical ointment, solution, shampoo or scrub. So instead of having a standard dose, povidone iodine is generally applied to the area you want to disinfect, such as an open wound.
The dose for potassium iodide depends on its use. The usual adult dose for treating cough is between 300 and 650 mg taken three to four times daily, according to Drugs.com. Treating cough in children requires a dose of 60 to 250 mg taken four to six times a day. Hypothyroidism is treated with 250 mg doses given three times a day. This dose is usually administered about 10 to 14 days prior to thyroid surgery. The potassium iodide dose for treating exposure to radiation greater than or equal to 5 cGy is 130 mg/d for pregnant and lactating women. People between 18 and 40 that have been exposed to radiation levels of 10 cGy and up need 130 mg/d. The adult dose for treating cutaneous sporotrichosis is between 250 mg and 500 mg given three times daily. Treatment for this condition usually lasts between 6 and 12 weeks.
Proper Use
When using povidone iodine, prevent the solution from making contact with your eyes, nose or mouth. The antiseptic is meant to be used on small areas at a time. Avoid using povidone iodine solution over large areas of your body. Do not use it for longer than a week unless otherwise instructed by your doctor. Seek medical advice before using povidone iodine on serious burns as well as on deep wounds or puncture wounds.
Measure potassium iodide doses with a dose-measuring spoon or cup to ensure you take the correct dose. Take potassium iodide regularly as instructed by your doctor in order to benefit from its use. Potassium iodide is harmful to unborn babies, Drugs.com says. Pregnant and breastfeeding women should avoid taking potassium iodide to avoid potential side effects and adverse reactions to both themselves and their babies. Never exceed the dose prescribed by your doctor because this elevates your risk of overdose. Seek immediate medical attention if you suspect that you have overdosed on potassium iodide.
Side Effects and Adverse Reactions
Potassium iodide and povidone iodine have been associated with skin irritation and rashes, according to Drugs.com. Other povidone iodine side effects include itching, breathing difficulties and swelling of the facial area.
Potassium iodide sometimes causes arrhythmia, confusion, fever, nausea, gastrointestinal bleeding and stomach upset, MerckManual.org explains. Prolonged treatment or exposure to high doses of potassium iodide leads to chronic iodine poisoning.
