Iodine is a chemical element. Betadine is a brand name for povidone-iodine, a preparation in which iodine is bound to a carrier so it releases slowly and stings far less than the old tincture. Betadine contains iodine; iodine is not Betadine.
The core difference
- iodine — element 53, a halogen. Essential in the diet, and antiseptic in solution.
- Betadine — a trademark for povidone-iodine, an iodophor: iodine complexed with a polymer carrier.
Why the carrier matters
Old-fashioned tincture of iodine was iodine dissolved in alcohol. It worked, but it stung sharply, stained heavily and could irritate tissue. Binding iodine to povidone releases it gradually instead of all at once, which keeps the antiseptic action while cutting the sting and the tissue damage. It is also why the brown colour washes out more readily than the old tincture did.
Brand and generic
This is the same relationship as paracetamol and Panadol, or ibuprofen and Nurofen. Povidone-iodine is the generic name and is sold under many brands worldwide. Betadine is one of them, and like Hoover or Biro it is often used generically in speech.
Iodine as a nutrient
Separate from any antiseptic use, iodine is required to make thyroid hormones. Deficiency causes goitre and, in severe cases during development, serious harm. Iodised salt was introduced specifically to address this and is one of the more effective public health measures of the twentieth century. Seafood, dairy and seaweed are the main dietary sources.
The other iodine words
- Lugol's iodine — iodine and potassium iodide in water. Used in medicine and in food preparation in some traditions.
- Iodide — the ion. Potassium iodide tablets are stocked for radiological emergencies, where saturating the thyroid blocks uptake of radioactive iodine.
- Iodophor — the general class Betadine belongs to.
Where the name comes from
Iodine is from Greek iodes, violet-coloured, because the element gives off a striking violet vapour when heated. It was discovered in 1811 by a French manufacturer processing seaweed for saltpetre, who noticed the purple fumes.
This page explains the words, not treatment. Wound care is a matter for a pharmacist or doctor.
Frequently asked questions
Is Betadine the same as iodine?
No. Iodine is the element. Betadine is a brand of povidone-iodine, in which iodine is bound to a carrier so it releases slowly and stings less.
Why does Betadine sting less than iodine tincture?
Because the iodine is complexed with povidone and released gradually, rather than dissolved in alcohol and delivered all at once.
Why is iodine added to salt?
Iodine is required to make thyroid hormones, and deficiency causes goitre and developmental harm. Iodised salt was introduced to address this.