What should you know about hereditary ichthyosis?

The skin does not shed its outer cells normally, so scale can build up and the surface may feel rough, tight or cracked. Several inherited forms exist, and their appearance and severity differ. Changes may be most noticeable on the arms, legs, trunk or scalp. Heat, sweating, dry air and friction can make discomfort more noticeable, while cracks may allow irritation or infection.

The condition is not caused by poor hygiene and is not something you can pass to another person through ordinary contact. A dermatologist may examine the pattern, ask when it began, and review family history to distinguish it from acquired scaling disorders.

Use a gentle, fragrance-free cleanser and keep showers brief with lukewarm water. Apply a thick moisturiser soon after washing, then reapply when the skin feels tight. Products containing urea, lactic acid or other scale-softening ingredients may help some people, but irritated or cracked skin can sting.

Do not scrape forcefully or use harsh exfoliating tools. A dermatologist can tailor an emollient plan, prescribe medicines that loosen scale when appropriate, and check areas that repeatedly crack. See [Emollient Therapy](/treatments/medical-dermatology/emollient-therapy/) for more on moisturising treatment; related symptoms include [Dry Skin](/symptoms/dry-skin/) and [Scaly Skin](/symptoms/skin-scaling/).

Arrange a dermatology review if scaling is widespread, newly worsening, interfering with sleep or movement, or difficult to manage with moisturiser. Seek prompt medical care for increasing redness, warmth, swelling, pus, fever, painful fissures, or reduced sweating with dizziness or overheating. A child with extensive scaling, feeding difficulty or unusual sleepiness needs timely assessment.

Could this be an inherited form, and does the pattern suggest a particular type? Which moisturiser ingredients suit my skin? How should I care for cracks, and which signs suggest infection? Should relatives or children be assessed?