Dapsone
Dapsone: instructions for use and reviews
- 1. Release form and composition
- 2. Pharmacological properties
- 3. Indications for use
- 4. Contraindications
- 5. Method of application and dosage
- 6. Side effects
- 7. Overdose
- 8. Special instructions
- 9. Application during pregnancy and lactation
- 10. Use in childhood
- 11. In case of impaired renal function
- 12. For violations of liver function
- 13. Use in the elderly
- 14. Drug interactions
- 15. Analogs
- 16. Terms and conditions of storage
- 17. Terms of dispensing from pharmacies
- 18. Reviews
- 19. Price in pharmacies
Latin name: Dapson
ATX code: J04BA02
Active ingredient: dapsone (Dapsone)
Manufacturer: FGUP SPC "Pharmzashchita" (Russia)
Description and photo update: 2019-21-05
Prices in pharmacies: from 1364 rubles.
Buy
Dapsone is an antimicrobial agent.
Release form and composition
Dosage form - tablets: round, flat-cylindrical, almost white or white, with a chamfer, score and engraving "D" on one side (in a blister contour package 10 tablets, in a cardboard box 5 or 10 packs; in a can of high density polyethylene with screw cap 500 or 1000 tablets, in a carton box 1 can. Each box also contains instructions for the use of Dapson).
Composition of 1 tablet:
- active substance: dapsone - 50 mg;
- additional ingredients: colloidal silicon dioxide, povidone K-25, magnesium stearate, microcrystalline cellulose, crospovidone.
Pharmacological properties
Pharmacodynamics
Dapsone is an antileprosy drug with a bacteriostatic effect from the sulfone group. Pharmacologically active against pathogenic microflora, especially Pneumocystis jirovecii, Plasmodium and Mycobacterium leprae. In the latter case, the minimum inhibitory concentration (MIC) is nanograms, therefore, with leprosy, the therapeutic effect can be achieved with a daily dose of 25 mg of dapsone.
It is assumed that the mechanism of action of the drug has at least two points of application: the first is the formation of an analogue of dihydropteric acid (dapsone is absorbed instead of p-aminobenzoic acid) and the second is inhibition of the enzyme dihydropteroate synthetase. As a result of these processes, functional impairment of other systems is possible, for example, dihydrofolate reductase, the function of which is to convert dihydrofolic acid, which is not used by microorganisms, into tetrahydrofolic acid.
In addition to its antibacterial effect, other factors determine the effect of dapsone. In particular, the drug slows down the production of cytotoxic radicals in the chain "myeloperoxidase - hydrogen peroxide - halogenated compounds".
There is information about other effects of dapsone, such as inhibition of the Artus reaction and the complement system when it is activated by an alternative pathway, inhibition of the binding of leukotriene B 4 to its specific receptors, inhibition of some lysosomal enzyme systems and the reaction of erythrocytes to phytohemagglutinin.
In experimental conditions, among other things, the anti-inflammatory and analgesic effect of dapsone, its effect on the immune system, was revealed.
Pharmacokinetics
When taken orally from the gastrointestinal tract, dapsone is absorbed almost completely (up to 80%). After 2-6 hours, it reaches its maximum plasma concentration (C max). When a daily dose of 100 mg is prescribed, the plasma concentration with a single dose is 1.7 mg / l, in an equilibrium state - 3.3 mg / l, after 24 hours it decreases to 0.7 mg / l.
The connection with plasma proteins is 70-90%. Dapsone penetrates well into various organs and tissues of the body, where it creates concentrations approximately equal to plasma ones. The drug is also able to penetrate into the intracellular space of phagocytes.
The average half-life (T 1/2) is 30 hours. After taking a dose of 100 mg, about 90% of the drug is completely excreted after ~ 9 days. However, with continued therapy, dapsone is found in the body for up to 35 days after the last dose. In this case, the relative cumulation is not observed.
The drug is metabolized by acetylation in the liver, as well as by hydroxylation. It is believed that the metabolite monohydroxylamine dapsone is responsible for side effects from the blood system.
The substance differs in hepatoenteric circulation. Approximately 90% is excreted by the kidneys (mainly in the form of metabolites), about 10% of the dose is excreted through the intestines.
Indications for use
- leprosy (in combination with other anti-leprosy agents);
- bullous pemphigoid and Duhring's dermatitis herpetiformis (in case of mild course - as a monopreparation, in case of severe course - in conjunction with immunosuppressants and glucocorticosteroids);
- vasculitis (in some cases; as part of combination therapy).
Contraindications
Absolute:
- severe liver disease;
- porphyria;
- deficiency of glucose-6-phosphate dehydrogenase;
- severe anemia (hemoglobin level <70 g / l);
- age up to 18 years;
- lactation period;
- hypersensitivity to dapsone, tablet auxiliary components, sulfones or sulfonamides.
With care: pregnancy, old age, impaired renal and liver function.
Dapsone, instructions for use: method and dosage
Dapsone tablets should be taken orally, preferably after meals with plenty of water.
Recommended regimen of intake: every day, except for one day a week, for example, Sunday.
The optimal dosage regimen is determined individually, depending on the clinical situation. On average, 1-2 tablets are prescribed per day, six times a week (for example, from Monday to Saturday, Sunday is a day off).
If the doctor does not provide for an individual dosing regimen, the following doses and duration of administration are recommended, depending on the diseases:
- leprosy: 50–100 mg per day, the course of treatment is several years;
- Dühring's dermatitis herpetiformis: the initial dose is 100 mg 2 times a day for 1 week, then, if necessary, the dose is increased to 200 mg. In some cases, a daily dose of 300 mg is allowed for a short time. In all cases, it is recommended to strive for the lowest dose (50 mg); to achieve the desired effect, the combination of Dapsone with glucocorticosteroids (GCS) is allowed. The treatment is long-term, it can reach several years. When taking GCS together between courses of treatment, the intervals are increased, the necessity and duration of which is determined by the doctor in each case individually;
- bullous pemphigoid: 100-150 mg per day;
- vasculitis: 50-150 mg per day.
With the development of undesirable symptoms from the digestive system, a decrease in the dose of the drug may be facilitated by the appointment of a gluten-free diet.
Side effects
- on the part of the immune system: the development of the so-called dapsone syndrome, manifested by symptoms such as feeling unwell, fever, skin rashes, jaundice, exfoliative dermatitis, erythema multiforme, anemia, methemoglobinemia, mononucleosis, swollen lymph nodes;
- from the circulatory system: eosinophilia, hemolytic anemia, agranulocytosis, methemoglobinemia;
- from the nervous system: visual impairment, dizziness, insomnia, psychosis, peripheral neuropathy (including motor);
- others: abdominal pain, nausea, vomiting, pancreatitis, nephrotic syndrome, headache, systemic lupus erythematosus, papillary necrosis, phototoxicity, fever, albuminuria, hypoalbuminemia without proteinuria, tachycardia, infertility in men, similar to infectious mononucleosis syndrome at the beginning of the course and as treatment continues, gradually disappear).
Overdose
Dapsone intoxication can manifest itself with the following symptoms: cyanosis, headache, nausea, vomiting, dyspnea, loss of vision, hematuria, methemoglobinemia, renal failure, hemolysis, tachycardia, disorders of the nervous system and psyche, coma.
There are no exact data on the doses of the drug that are lethal to humans. There is a known case where a dose of 1400 mg was fatal, and another patient survived after taking 15,000 mg of dapsone.
In case of taking an excessive dose, gastric lavage is performed first. Over the next few days, the patient is given activated charcoal, and if necessary, a laxative (20 ml of a 20 - 40% sorbitol solution). To enhance the excretion of sulfone and the prevention of renal failure, infusion therapy is indicated (the introduction of a sufficient amount of liquid with diuretics and sodium bicarbonate to alkalinize urine). For methemoglobinemia, methylene blue 1% (intravenous 0.2 ml / kg) and / or vitamin C are administered.
In case of severe overdose, hemodialysis begins as early as possible. Shown are blood transfusion, infusion of erythrocyte mass, oxygen therapy, if necessary - artificial respiration under the control of the amount of oxygen tension in the blood. For other disorders, symptomatic therapy is performed.
special instructions
During the entire period of treatment, it is necessary to systematically monitor the state of the blood (do a clinical analysis): at the initial stage - every week, then - every month. With a significant decrease in the level of hemoglobin, leukocytes and platelets or an increase in the content of methemoglobin, Dapsone is canceled. If the concentration of methemoglobin in the blood increases to ≥ 10%, cyanosis develops, to ≥ 30% - shallow breathing. The patient should be warned about the need for immediate medical attention if bluish discoloration of the nails and / or lips appears.
In patients with severe anemia, the drug can be prescribed only for health reasons (for example, for the treatment of Duhring's dermatitis herpetiformis). In this case, therapy should be carried out with caution, under close monitoring of the hemoglobin level.
If a skin rash appears, you should immediately discontinue the drug and consult a doctor.
Influence on the ability to drive vehicles and complex mechanisms
Based on the available data, Dapsone's negative effects on cognitive and psychomotor functions are unlikely.
Application during pregnancy and lactation
During pregnancy, especially in the first 4 months, Dapsone 50 mg tablets are used with extreme caution if the expected benefit outweighs the potential risk.
If therapy is necessary during lactation, breastfeeding should be abandoned.
Pediatric use
Dapsone is not used to treat patients under the age of 18.
With impaired renal function
In patients with impaired renal function, the drug is used with caution.
For violations of liver function
In severe functional disorders of the liver, the use of Dapsone is contraindicated. Caution is required for moderate impairments.
Use in the elderly
In elderly patients, side effects from the blood system are usually more pronounced, so treatment is carried out with caution.
Drug interactions
Probenecid reduces the excretion of dapsone and increases its content in the blood.
With the simultaneous use of trimethoprim, it is possible to change the concentration of both drugs in the blood.
Dapsone enhances the action of rifampicin, isoniazid and prothionamide, so that their doses can be reduced, especially prothionamide.
Pyrimethamine is able to change the volume of distribution of dapsone, its concentration in plasma and saliva.
Rifampicin increases the plasma clearance of the drug, resulting in a 7–10-fold decrease in the concentration of dapsone.
Simultaneous reception with cimetidine and ethanol in moderate amounts does not affect the absorption of the drug.
Analogs
Dapson's analogue is Dapson-Fatol.
Terms and conditions of storage
Store at a temperature not exceeding 25 ° C in a dry, protected from light, out of reach of children.
The shelf life is 3 years.
Terms of dispensing from pharmacies
Dispensed by prescription.
Reviews about Dapsone
Most often, reviews about Dapsone are left by patients to whom it was prescribed for the treatment of Duhring's dermatitis. The effectiveness of therapy is noted, however, the expressed toxicity of the drug. It can be reduced by the simultaneous administration of ascorbic acid, iron preparations and methyluracil.
Of the side effects, headache, indigestion, loss of appetite, anemia and agranulocytosis are mainly mentioned.
Dapsone price in pharmacies
The current price for Dapsone 50 mg for a pack of 100 tablets is approximately 1,498-1554 rubles.
Dapsone: prices in online pharmacies
|
Drug name Price Pharmacy |
|
Dapsone 50 mg tablets 100 pcs. 1364 RUB Buy |
|
Dapsone tablets 50mg 100 pcs. 1475 RUB Buy |
Anna Kozlova Medical journalist About the author
Education: Rostov State Medical University, specialty "General Medicine".
Information about the drug is generalized, provided for informational purposes only and does not replace the official instructions. Self-medication is hazardous to health!
