Sodium Intake for Atopic Dermatitis and Psoriasis

(SIS-ISD Trial)

This trial explores how altering salt intake affects skin conditions such as atopic dermatitis and psoriasis. Researchers aim to determine if a link exists between sodium levels in the skin and the severity of these conditions. Participants will alternate between consuming sodium chloride tablets (salt tablets) and placebo pills while adhering to a low-salt diet. This trial suits adults with atopic dermatitis or psoriasis who can undergo an MRI and are not affected by specific medical conditions or medications. As a Phase 4 trial, the treatment is already FDA-approved and proven effective, aiming to understand how it benefits more patients.

You may need to stop certain medications, especially those that affect sodium excretion or if you've taken antibiotics or immunomodulatory drugs in the last month. However, some topical treatments and stable doses of eczema medications are allowed. There is a 2-week period without taking sodium tablets or placebo, known as a washout period.

Research has shown that excessive salt intake might affect skin problems like eczema and psoriasis. This study focuses on salt tablets. Some research suggests that high salt levels can increase certain immune cells, possibly worsening skin issues. However, these studies did not involve human participants.

Regarding safety, salt is a common part of the diet, suggesting that this treatment is likely safe when used carefully. However, excessive salt can cause issues like high blood pressure or swelling in some individuals.

Most treatments for atopic dermatitis and psoriasis, like topical corticosteroids and biologics, work by reducing inflammation or modifying the immune system. But sodium chloride tablets offer a unique approach by potentially influencing skin conditions through dietary sodium regulation. Researchers are excited because this treatment could represent a simple, oral addition to current therapies, possibly offering relief with fewer side effects. This novel method of managing skin inflammation through sodium intake is what makes it stand out from traditional options.

Research has shown that people with atopic dermatitis, a condition causing itchy and inflamed skin, have much higher sodium levels in their skin compared to those without it. One study found sodium levels in the skin were 30 times higher in individuals with this condition. Another study suggested that reducing sodium intake might lower the chances of flare-ups in atopic dermatitis. For psoriasis, which causes red, scaly skin patches, higher sodium consumption was linked to an 18% increased risk of developing the condition. Lab studies indicate that sodium might activate certain immune cells, worsening these skin conditions. Therefore, managing sodium intake could be important in treating atopic dermatitis and psoriasis. This trial will compare the effects of sodium chloride tablets and placebo tablets on these conditions, with participants receiving both treatments in different sequences.¹⁴⁶⁷⁸