- What other names is Iodine known by?
- What is Iodine?
- How does Iodine work?
- Are there safety concerns?
- Are there any interactions with medications?
- Dosing considerations for Iodine.
The thyroid gland needs iodine to make hormones. If the thyroid doesn't have enough iodine to do its job, feedback systems in the body cause the thyroid to work harder. This can cause an enlarged thyroid gland (goiter), which becomes evident as a swollen neck.
Other consequences of not having enough iodine (iodine deficiency) are also serious. Iodine deficiency and the resulting low levels of thyroid hormone can cause women to stop ovulating, leading to infertility. Iodine deficiency can also lead to an autoimmune disease of the thyroid and may increase the risk of getting thyroid cancer. Some researchers think that iodine deficiency might also increase the risk of other cancers such as prostate, breast, endometrial, and ovarian cancer.
Iodine deficiency during pregnancy is serious for both the mother and the baby. It can lead to high blood pressure during pregnancy for the mother, and mental retardation for the baby. Iodine plays an important role in development of the central nervous system. In extreme cases, iodine deficiency can lead to cretinism, a disorder that involves severely stunted physical and mental growth.
Iodine deficiency is a common world health problem. The most recognized form of deficiency is goiter. Additionally, across the globe iodine deficiency is thought to be the most common preventable cause of mental retardation. Early in the twentieth century, iodine deficiency was common in the US and Canada, but the addition of iodine to salt has improved public health. The addition of iodine to salt is required in Canada. In the US, iodized salt is not required, but it is widely available. Researchers estimate that iodized salt is used regularly by about half the US population.
Iodine is used to prevent iodine deficiency and its consequences, including goiter. It is also used for treating a skin disease caused by a fungus (cutaneous sporotrichosis); treating fibrocystic breast disease; preventing breast cancer, eye disease, diabetes, and heart disease and stroke; and as an expectorant.
Iodine is also used to for radiation emergencies, to protect the thyroid gland against radioactive iodides. Potassium iodide tablets for use in a radiation emergency are available as FDA-approved products (ThyroShield, Iosat) and on the Internet as food supplements. Potassium iodide should only be used in a radiation emergency, not in advance of an emergency to prevent sickness.
Iodine is applied to the skin to kill germs, prevent soreness inside the mouth (mucositis) caused by chemotherapy, and treat diabetic ulcers.
Iodine is also used for water purification.
Likely Effective for...
- Iodine deficiency. Taking iodine supplements, including iodized salt, is effective for preventing and treating iodine deficiencies.
- Radiation exposure. Taking iodine by mouth is effective for protecting against exposure to radioactive iodides in a radiation emergency.
- Thyroid conditions. Taking iodine by mouth can improve thyroid storm and hyperthyroidism. Also, taking iodized salt in addition to thyroxine after surgery for thyroid disease appears to reduce the size of the thyroid.
- Leg ulcers. Research suggests that applying cadexomer iodine to venous leg ulcers along with compression for 4-6 weeks increases the healing rate. Also, applying povidone-iodine in addition to compression seems help heal leg ulcers and reduce the chance of a future infection.
Possibly Effective for...
- Catheter-related infection. Some evidence suggests that applying povidone-iodine reduces the risk of blood stream infections for people with hemodialysis catheters. However, other research suggests that applying povidone-iodine where a catheter is inserted does not reduce the risk of infection associated with using other types of catheters.
- Conjunctivitis (pinkeye). Research suggests that povidone-iodine solutions are more effective than silver nitrate for decreasing the risk of pinkeye in newborns. However, it is not more effective than the medications erythromycin or chloramphenicol.
- Foot ulcers in diabetes. Applying iodine to foot ulcers might be beneficial for people with foot ulcers related to diabetes.
- Inflammation of the uterus (endometritis). Applying povidone-iodine solution to the vaginal area before a Cesarean delivery reduces the risk of the inflammation of the uterus.
- Painful fibrous breast tissue (fibrocystic breast disease). Research shows that taking iodine, especially molecular iodine, reduces painful fibrous breast tissue.
- Breast pain (mastalgia). Taking iodine tablets daily for 5 months reduces pain and tenderness in women with breast pain related to their menstrual cycle.
- Soreness and swelling inside the mouth. Applying iodine to the skin seems to prevent soreness and swelling inside the mouth caused by chemotherapy.
- Gum infection (periodontitis). Research suggests that rinsing with povidone-iodine during non-surgical treatments for gum infections (periodontitis) can help reduce the depth of infected gum pockets.
- Surgery. Some research suggests that applying povidone-iodine during surgery reduces the risk of infections. However, povidone-iodine seems to be less effective than chlorhexidine at preventing infections at the surgical site.
Insufficient Evidence to Rate Effectiveness for...
- Bleeding.Early research suggests that washing the tooth socket with povidone-iodine stops bleeding in more patients after having a tooth pulled compared to saline.
- Chyle in the urine (chyluria). Early research suggests that using povidine-iodine in people with chyle in the urine undergoing a pelvic instillation sclerotherapy may be as effective as standard care.
- Eye infection (corneal ulceration). Early evidence suggests that administering povidone-iodine in addition to standard antibiotic therapy does not improve vision in people with corneal ulcers.
- Fungal skin condition (Cutaneous sporotrichosis). Potassium iodide is commonly used for cutaneous sporotrichosis. There are reports that taking potassium iodide by mouth alone or with another antifungal treatment is effective for most people with cutaneous sporotrichosis.
- Pneumonia. Early research suggests that rinsing the throat with povidone-iodine decreases the risk of pneumonia in people with severe head trauma who are using a ventilator.
- Wound healing. There is some interest in using iodine agents to promote wound healing. While there is some evidence that applying iodine to wounds is more effective than non-antiseptic dressings in reducing wound size, iodine seems to be less effective than antibiotics.
- Other conditions.
Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).
Next: How does Iodine work?
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