Sulfoxone

Sulfoxone, also known as Aldesulfone sodium, is a synthetic sulfone drug formerly used in the treatment of leprosy. It is a prodrug that is converted in the body to dapsone, the active antimicrobial agent.

Mechanism of Action: Sulfoxone acts as a prodrug, requiring metabolism to dapsone to exert its therapeutic effects. Dapsone inhibits the enzyme dihydropteroate synthase (DHPS), a crucial enzyme in the folate synthesis pathway of bacteria and protozoa. By inhibiting DHPS, dapsone interferes with the synthesis of tetrahydrofolic acid, a vital cofactor necessary for the synthesis of purines, pyrimidines, and certain amino acids. This ultimately inhibits the growth and reproduction of susceptible microorganisms, including Mycobacterium leprae.

Historical Use: Sulfoxone was used in the mid-20th century as a treatment for leprosy (Hansen's disease). However, it has largely been superseded by dapsone itself and multidrug therapy (MDT) regimens that combine dapsone with other anti-leprosy drugs like rifampicin and clofazimine. The shift away from sulfoxone was largely due to the availability of dapsone in a more easily administered form and the development of more effective and well-tolerated multidrug therapy approaches.

Administration: Sulfoxone was typically administered orally.

Adverse Effects: As sulfoxone is converted to dapsone, the adverse effects associated with its use were similar to those of dapsone. These include, but are not limited to:

• Hemolysis (especially in individuals with glucose-6-phosphate dehydrogenase deficiency)
• Methemoglobinemia
• Peripheral neuropathy
• Skin reactions, including allergic dermatitis
• Gastrointestinal disturbances

Note: Sulfoxone is not widely used in modern medicine. Information about its use is primarily of historical interest.