Dapsone is an active substance of the sulfones group. The substance has antimicrobial and anti-inflammatory effects. Dapsone is primarily administered in tablet form and is used to treat rheumatism, acne, blistering skin diseases, inflammatory skin diseases, and malaria or leprosy.
What is dapsone?
Dapsone is a drug that has anti-inflammatory and antibacterial effects. The substance belongs to the group of sulfones. Due to its antibacterial effects, it is also classified as an antirheumatic agent. The medicinal agent was first synthesized in Germany in 1908 and patented by I. G. Farben in 1934. The white (sometimes yellowish white) powder is often used in tablet form and is used to treat rheumatic diseases. It is just as often administered as a preventive to combat leprosy, inflammatory skin diseases, malaria, and pneumocystis pneumonia in patients who are HIV-positive. In addition to the name dapsone, the synonyms diphenasone, diaminodiphenylsulfone, DDS, and dapsonum are also used to describe the substance. The chemical formula of the drug is C12-H12-N2-O2-S, Mr, which corresponds to a moral mass of 248.3 g/mol. While in Europe it is only approved in tablet form, in the USA it may also be used as a gel. Here, it is used to treat acne.
Pharmacological action
Dapsone exerts antibacterial effects against the bacteria Mycobacterium tuberculosis and Mycobacterium leprae (causative agents of leprosy) and against streptococci. In addition, it is effective against parasites (atiparasitic effect), protozoa and plasmodia. In addition, dapsone inhibits inflammation. Dapsone acts directly on the synthesis of folic acid in bacteria. This results in an antimetabolic inhibition of folic acid synthesis, which ultimately leads to the killing of the affected bacteria. Since dapsone was first administered, there have been various developments of resistance to the drug, so the active ingredient is primarily used in combination therapy. Patients therefore usually take additional preparations containing clofazimine or rifampin. As the listing of dapsone, in the European Regulation (EU) No. 37/2010 shows, the substance may not be used in animals that are processed into food in the European Union. The reason given for this listing is that the substance has high maximum residue limits.
Medical application and use
Dapsone has a very broad field of application in human medicine due to its broad spectrum of activity. In the European Union, there is a marketing authorization exclusively for administration in tablet form. There is an indication for the treatment of inflammatory skin diseases and those that form blisters. There is also an indication for chronic rheumatic diseases of the joints (articular rheumatism), malaria, rheumatism, leprosy and Pneumocystis pneumonia (a special pathogen of pneumonia in humans). The medical term indication is used to describe the fact that administration for therapeutic purposes is indicated from a medical point of view. For the control of Pneumocystis pneumonia, dapsone is primarily used in patients who are HIV-positive. In the treatment of leprosy disease, dapsone is always combined with other drugs. In the United States of America, dapsone is also approved for administration as a gel. This is applied locally to the skin to treat acne vulgaris. Furthermore, other areas of application are recommended in the medical literature, but there is no approval for these yet, so that in practice no administration is carried out yet.
Risks and side effects
As with most drugs, adverse side effects may occur with the administration of preparations containing dapsone. Therefore, before any first-time use, it should be checked whether there is any intolerance or hypersensitivity to dapsone as well as similar substances. For example, hypersensitivity to sulfonamides and severe liver disease are contraindications. This means that, from a medical point of view, the use of dapsone must be avoided, as there is a contraindication.In addition, special caution is required when taking dapsone if there is a hereditary deficiency of glucose-6-phosphate dehydrogenase, anemia, bluish discoloration of the lips or fingernails, skin rashes, or pregnancy. During breastfeeding, it is mandatory to stop breastfeeding. There are also interactions with omeprazole (a drug that inhibits the formation of stomach acid), trimethoprim (an antibacterial drug), rifampicin (a tuberculosis drug), pyrimethamine (an antimalarial drug), and ursodeoxycholic acid (a drug used to dissolve gallstones). If these drugs are taken, the attending physician must be informed immediately. During therapy with dapsone, headache, stomach discomfort or nausea may occur frequently (in 1 to 10 treated persons out of 1000). In rare cases, bluish discoloration of the skin and anemia (lack of protein in the blood) occur. Rarely means that this was the case in 1 to 10 treated people out of 10,000. Dapsone syndrome may develop, especially in poorly nourished patients. Very rarely, white blood cell loss (agranulocytosis) occurred. Very rarely means that this occurred in less than one patient in 10,000. If side effects occur, the attending physician should be informed immediately. Instructions should be followed urgently.
