Preservative

Sodium Iodide

INCI: SODIUM IODIDE

Reviewed by Rosie · Last updated 14 Aug 2026

An inorganic salt with established purifying properties for use in skincare formulations

Best For Skin Types

All

Addresses

Acne

Usage Frequency

As directed by product instructions

What Is Sodium Iodide?

Sodium iodide is an inorganic salt composed of sodium and iodine. It occurs naturally in seawater and mineral deposits, and has been used in cosmetic and pharmaceutical formulations for its antimicrobial activity.

In skincare, sodium iodide functions primarily as a preservative and antimicrobial agent, helping to inhibit the growth of bacteria and other microorganisms that can compromise product stability and skin health.

How It Works

Sodium iodide exerts its antimicrobial effect through the release of iodine, which penetrates microbial cell membranes and disrupts their metabolic processes. This prevents bacteria and other microorganisms from multiplying, making it useful both as a preservative within the product and potentially as a topical antimicrobial agent on the skin.

Clinical Evidence & References

Iodine-based compounds, including potassium iodide, have a long history of use in dermatology, particularly for treating certain skin infections. However, research specifically on sodium iodide in topical skincare is limited. Some evidence suggests iodine compounds may have anti-inflammatory properties, though this requires further investigation in the context of sodium iodide specifically.

Most published research focuses on iodine's broader antimicrobial and immunomodulatory effects rather than sodium iodide in cosmetic formulations. More studies would clarify its efficacy and optimal use in skincare products.

How to Use

Sodium iodide is typically used in formulations rather than as a standalone product. If using skincare products containing this ingredient, follow the product's application instructions. For those with iodine sensitivity or certain thyroid conditions, it is sensible to patch test first and consult a healthcare provider if concerns arise.

Safety & Precautions

Sodium iodide is generally well-tolerated at cosmetic concentrations. Individuals with iodine sensitivity, hyperthyroidism, or those taking thyroid medications should exercise caution and seek medical advice before use.

Frequently Asked Questions

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