Molecular Overview

Molecular Formula:
C12H12N2O2S

Molecular Weight:
248.302 Grams/Moles

Chemical Name:
4-(4-aminophenyl)sulfonylaniline

Drug Overveiw:
Diamino diphenyl sulfone

Dapsone: A Cure for Leprosy

Leprosy, a millennia old disease found throughout the world, is truly devastating, tearing apart families and communities. Caused by Mycobacterium leprae, leprosy affects the skin and peripheral nerves, slowly over the course of many years causing irreversible damage, in many cases leaving its victim with loss of feeling of limbs and skin lesions and heavily deformed. Over the ages, fear of the diseases has lead communities around the world, to forcefully disband countless victims from their ranks. Family-less, and outcasts, they turned to the only place where they were now accepted, with the other victims, forming what became known as Leper Colonies. However with incredibly few willing to come within any proximity to those effected, let alone offering help to those believed to have been cursed by god, lepers were forced to suffer the gruesome, tragic fate of struggling to make it by in isolation. In as early as 1200 AD there were as many as 19,000 leprosy cases in Europe alone, a number that only grew over time, swelling well into the millions in the nineteenth century.

In 1873 however the cause of the once mysterious, believed hereditary disease was discovered by pathologist Dr Gerhard A Hansen, a Norwegian pathologist, the bacteria Mycobacterium leprae. Even so, armed with this new-found knowledge, the prospect of finding a cure remained bleak, the International Leprosy Conference in 1897 itself, coming to the consensus that the disease was "incurable". The identification of the cause of this disease nevertheless resulted in a flurry of action to come-up this desperately needed cure. In the early twenty century the oil from the Chaulmoogra nut was proposed as one possible solution however worked with very limited success. Without any alternatives though, this treatment remained until in 1941 the sulfone drug Promin, was developed and used with effectiveness. It did however require multiple painful injection daily and so when in Diamino Diphenyl Sulphone (DDS) or Dapsone pills became available in the early 1950’s, an oral antibiotic proven to kill M. leprae, it became the leading treatment.

However by the time dapsone was officially approved by the Food and Drug Administration on July 3, 1979, in the form oral 25 and 100mg tables, dapsone resistant M. leprae had already began to appear. To combat this new strain of bacteria, dapsone doses began being taken with the weaker, more recently developed antibiotics rifampicin and clofazimine to effectively inhibit the spread of disease. Dapsone, absorbed through the gastrointestinal tract, achieves its effectiveness through inhibiting the production of Folinic acid, a chemical essential in the production of DNA, without which M. leprae cannot reproduce. Clofazimine and Rifampicin work through similar prosses to Dapsone, clofazimine through interfering with the bacteria's production of DNA and the latter through inhibiting the bacterial synthesis of RNA.

Dapsone Today

Through extensive and rigorous employment of Dapsone and its counter-parts in Multidrug Therapy, the number of Leprosy cases in the world has fallen dramatically. From an estimated peak of ten to twelve million cases worldwide the total number has plummeted over the decades to a mere 211,903 in 2010. A “final push” strategy facilitated by the World Health Organization is currently under way to get the leprosy prevalence rate below one in every 10,000 people in all countries. In an attempt to achieve this goal, in 1995, WHO made treatment of leprosy free to all those that could not afford it. Currently the only supplier of Dapsone worldwide is the Jacobus Pharmaceutical Company, located in Princeton, New Jersey.

Side-Effects and Other Uses of Dapsone

Although the benefits of dapsone vastly outweigh its side-effects, the drug does have some side-effects including:

• Headache
• Difficulty in sleeping
• Inflammation of the liver
• Nausea and vomiting
• Loss of appetite
• Reduced numbers of red blood cells
• Rash with a fever and a decrease in the number immune cells (Often referred to as Dapsone syndrome)

In addition to treating leprosy, Dapsone has a wide range of other secondary, more obscure uses. Dapsone has been known to treat Behcet's disease, Cicatricial pemphigoid, Erythema elevantum diutinum, Mycetoma, Pemphigus herpetiformis, Black Widow spider bites and many others. Dapsone can also when administered with Chlorproguanil prevent uncomplicated malaria and even act as an anti-acne gel under the brand name Aczone.

Bibliography

"Dapsone." NetDoctor. N.p., n.d. Web. 27 Oct. 2010.
http://www.netdoctor.co.uk/infections/medicines/100000679.html>.

"Leprosy: the disease." World Health Organization. N.p., n.d. Web. 26 Oct. 2010.
http://www.who.int/lep/leprosy/en/index.html>.

MD, PhD Davis, Charles. "Leprosy (Hansen's Disease)." MedicineNet. N.p., n.d.
Web. 27 Oct. 2010. http://www.medicinenet.com/leprosy/article.htm>.

Sein, Than, and Kyaw Lwin. "A Million Smiles: Eliminating Leprosyin South-East
Asia." World Health Organization: Regional Office for South-East Asia.
N.p., n.d. Web. 27 Oct. 2010. http://www.searo.who.int/en/Section1243/
Section1310/Section1343/Section1344/Section1357_5342.htm>.

"Understanding Leprosy." Rising Star Outreach. N.p., n.d. Web. 27 Oct. 2010.
http://www.risingstaroutreach.org/understandingleprosy>.

"WHO Multidrug therapy (MDT)." World Health Organization. N.p., n.d. Web. 26
Oct. 2010. http://www.who.int/lep/mdt/en/index.html>.

Wolf, Ronni, et al. "Dapsone." Dermatology Online Journal. N.p., n.d. Web. 11
Nov. 2010. http://dermatology.cdlib.org/DOJvol8num1/reviews/dapsone/wolf.html#25>.