Suplatast tosylate is primarily used as an antiallergic agent, particularly in the treatment of bronchial asthma, allergic rhinitis, and atopic dermatitis. It works by inhibiting the production of immunoglobulin E (IgE) and suppressing the release of histamine from mast cells, which helps in reducing allergic reactions. The compound is effective in managing symptoms such as sneezing, nasal congestion, wheezing, itching, and swelling by modulating the immune response. Clinically, it is administered orally and is known for its ability to provide relief without causing significant sedation, making it a favorable option for patients requiring long-term allergy management. Additionally, suplatast tosylate has been explored for its potential anti-inflammatory properties, which could extend its use to other inflammatory conditions beyond allergies. Its mechanism of action and safety profile make it a valuable component in the therapeutic arsenal against allergic diseases.