Dapsone, or DDS, diaminodiphenylsulfone is the only effective treatment and prevention of leprosy and dermatitis herpetiformis. Less commonly used in the treatment of lichen planus, in the treatment and prevention of Pneumocystis pneumonia, in the prevention of toxoplasmosis, in the prevention of malaria and in the treatment of cutaneous leishmaniasis.
Indications for use of Dapsone
Dapsone is used by:
- for the treatment and prevention of all forms of leprosy (as part of combination therapy)
- for the treatment of Duhring's dermatitis herpetiformis
- for the treatment of lichen planus
- for the treatment and prevention of pneumocystis pneumonia
- for the prevention of toxoplasmosis
- for the prevention of malaria
- for the treatment of cutaneous leishmaniasis
Pharmacological action of Dapsone
Dapsone is an antileprosy agent from the group of sulfones, the mechanism of action is similar to sulfonamides: the drug inhibits the synthesis of folic acid of pathogens such as Mycobacterium leprae, Plasmodium, Pneumocystis carinii. In addition, the drug can act as an immunomodulator in the treatment of dermatitis herpetiformis.
Dapsone is slowly absorbed from the gastrointestinal tract. The bioavailability of the drug is 70-80%, although this figure may decrease in severe leprosy. Absorption increases in acidic environments.
Dapsone is distributed throughout all body fluids and is found in all tissues, although to a greater extent in the liver, muscles, kidneys and skin. The concentration of the drug in saliva is 18 -27% of its concentration in blood plasma. The drug crosses the placenta.
Dapsone in liver cells is metabolized by N-acetyltransferase to monoacetyl Dapsone, as well as by the oxidase system to Dapsone-hydroxylamine, a metabolite, responsible for the toxicity of the drug. However, both metabolites are inactive and do not mediate the therapeutic effect of Dapsone.
The elimination half-life is from 10 to 50 hours (on average - 30 hours), the maximum concentration is reached 2-6 hours after taking the drug.
Contraindications to the use of Dapsone
Hypersensitivity to Dapsone or its derivatives. Use the drug with extreme caution in patients with renal or hepatic insufficiency, as well as with deficiency of glucose-6-phosphate dehydrogenase.
If you experience any undesirable reactions, consult your doctor.
Dapsone should be used with caution in patients with heart, lung, liver or kidney disease.
With long-term therapy with Dapsone (Dapsone), it is necessary to monitor the state of the blood system due to the risk of developing hemolytic anemia. This is especially true for people with deficiency of glucose-6-phosphate dehydrogenase.
Interaction of Dapsone with other drugs
Rifampicin can increase the clearance of Dapsone, probenecid reduces the excretion of Dapsone. Co-administration of Dapsone and chloroquine (or primaquine) can lead to an increase in methemoglobin in individuals prone to methemoglobinemia.
Dapsone may interact with other drugs. Talk to your doctor if you start or stop taking other drugs or change the dosage.
Dapsone administration and dosage
Dapsone is taken as directed by a physician. The drug is available in the form of 100 mg tablets.
Usually, treatment should be continued for at least 6 months, however, it must be remembered that in all cases, without exception, the dosage and treatment regimen is determined only by a doctor.
Standard treatment regimens:
- Adults and children 15 years of age and older: standard dose 100 mg / once daily.
- Children 6-14 years old: 50-100 mg once daily.
- Children under 6 years of age: 25 mg once daily.
Duhring's dermatitis herpetiformis
Adults: The usual dose is 50 to 100 mg daily, but sometimes 50 mg is sufficient in Week. Perhaps a single appointment of the drug in a dose of up to 300 mg, then the dose is reduced.
Adults: Standard dose 100 mg / day.
Children: The dose depends on the weight of the child. Children from 10 to 14 years old are prescribed 50 mg or 1-2 mg / kg per day.
Modern anti-leprosy treatment includes several drugs in order to avoid the formation of resistant forms of bacteria.
Adults: rifampicin 600 mg once a month under medical supervision, Dapsone 100 mg daily alone, clofazimine 300 mg once a month under the supervision of a physician and 50 mg daily alone. With a relatively mild course, clofazimine is not prescribed.
Children: The doses of all three drugs are calculated according to the weight of the child. Dapsone is prescribed at a dose of 1-2 mg / kg.
Sulfone drugs are contraindicated in pregnancy.
The drug passes into breast milk and during breastfeeding can cause hemolytic anemia in newborns with deficiency of glucose-6-phosphate dehydrogenase.
Dapsone Side Effects
For most patients, taking Dapsone at therapeutic doses (up to 100 mg / day) does not cause side effects. Consult your doctor if adverse reactions persist or intensify, the most common of which are: anorexia, nausea, vomiting, headache, dizziness, tachycardia, insomnia and skin lesions.
See your doctor if you experience severe side effects such as agranulocytosis, peripheral neuritis, psychotic conditions, hemolysis and methemoglobinemia, as well as the so-called "Dapsone syndrome". It is a hypersensitivity reaction that rarely develops, usually in the first 6 weeks of therapy, and includes fever, eosinophilia, mononucleosis, lymphadenopathy, leukopenia, jaundice and hepatitis, as well as exanthemic skin lesions that can progress to exfoliative dermatitis, toxic epidermal necrolysis, or Stevens-Johnson syndrome. In these conditions, urgently consult a doctor to correct therapy.
At the first signs of inflammation, see your doctor. Patients receiving antileprosy treatment may develop acute or chronic inflammatory processes that need to be adequately treated without stopping the main therapy.
Not all possible side effects are listed above. If you have any questions or need medical attention about side effects, see your doctor.