In pharmacology, nitrofuran derivatives are used quite extensively. They are most relevant in identifying purulent processes and inflammations.
The most famous medicines
The most widely used nitrofuran derivatives in modern medical practice are:
- "Furagin."
- "Furazolidone."
- "Furacilin."
All of these medicines can be used as local antiseptics; oral forms have been developed. Derivatives of nitrofuran are approved for use, including by patients suffering from low tolerance to antimicrobial agents, sulfonamides.
Important Features
Derivatives of 5-nitrofuran exhibit a pronounced bacteriostatic effect. You can combine such drugs with antibiotics of the following categories:
- tetracycline series;
- erythromycin;
- preparations on oleandomycin.
Derivatives of nitrofuran are not intended for the treatment of persons undergoing therapy using:
- chloramphenicol;
- ristomycin-containing drugs;
- medicines with sulfonamides.
This is due to an increase in the negative effect on the hematopoietic system of the body.
How it works?
Quite often, nitrofuran derivatives are used to treat cystitis. This is due to the specific metabolism of the antimicrobial compound: the function lies on the kidneys, in which the medication accumulates. This makes it effective against a wide range of diseases characteristic of the urinary system. The indicated group of antibiotics helps well with various varieties of pyelonephritis.
Do not use nitrofuran derivatives and antiseptics, created with the participation of nalidixic acid, at the same time, since these two medicines inhibit the effect of one another. The specified uroantiseptic on sale is represented by the names:
Therapeutic program
Antiseptic agents (nitrofuran derivatives) are usually used three times daily in an amount of 0.1 g. The duration of such a program varies: at least 10 days, but not more than two weeks. It is known that in the treatment of Proteus, Pseudomonas aeruginosa invasion , the effectiveness of the drug is relatively low, but a pronounced effect is observed when eliminating the harmful coccal flora.
If infection is associated with the ingestion of gram-negative microscopic life forms, it is recommended to use nalidixic acid. The course of treatment lasts from 10 to 12 days, the drug is used daily in a two-gram dose. This treatment method is allowed if antibacterial treatment of the bile-removing pathways is required.
Is there an alternative?
You can replace derivatives of 5-nitrofuran with other synthetic medicines that can fight harmful microflora. Most often used:
- made on 8-hydroxyquinoline;
- quinoxaline based;
- products containing bis-quaternary ammonium compounds.
For sale, these groups are represented by the names:
- 5-NOC.
- "Mexform".
- "Dioxidine."
- Decamine.
- Enteroseptol.
Relative to the described group of drugs, these medicines have a different chemical structure and a fundamentally different composition. However, efficacy against infection initiators is similar. In many ways, therapy is justified by the lack of cross-resistance. You can resort to these funds if the patient has intolerance to nitrofuran-derived drugs.
Treatment of fungal infestation
To achieve maximum efficiency, nitrofuran derivatives are combined with agents such as:
The dosage is the same as that selected for antimicrobial agents. You can additionally use the antibacterial, antimycotic drug "Decamine".
When detecting generalized candidiasis, nitrofuran derivatives are enhanced with levrin sodium salt used twice or thrice daily. An alternative is the use of Amfoglucamine inside, parenterally Amphotericin B.
How to choose?
The doctor chooses a specific set of medications, focusing on the characteristics of a particular infection and the tendency to intolerance of some groups of drugs used in medicine. Not all pathogens show a sufficient level of sensitivity to nitrofuran derivatives so that the choice in favor of this category is always justified. It is important to consider the toxicity of the group of drugs and the ability to distribute in the tissues of the body, which varies significantly depending on the name.
Derivatives of nitrofuran in the general case are highly compatible with other medicines, but when patients undergo treatment, it is imperative to notify the doctor of all the drugs taken for a possible adjustment of the program. All allergic reactions and toxic effects characteristic of nitrofuran derivatives have been officially recorded. A special guide has been issued for doctors, detailing how to smooth out negative use results.
Release Features
Derivatives of nitrofuran include manufactured in the form of tablets "Furadonin." There are two dosage options: 0.05 g and twice as much. Recommended for use by a course lasting 5-8 days. It is applied three times or four times daily.
"Furazolidone" on sale is represented by an oral dosage form, the dosage is 0.05 g. It is recommended for use in a course lasting from five days to a twice as long period. Every day, the drug is taken 4 times.
Derivatives of nitrofuran also include the drug "Furagin." The form is tablets, the dosage is similar to the one described above - 0.05 g. Course duration, frequency of administration per day also coincide.
Finally, Solafur. In pharmacies, you can buy ampoules with a concentration of the active substance in a solution of 0.1%. The volume of one ampoule varies from 25 to 100 ml. The drug is intended for use through a dropper, the duration of the course is up to seven infusions (but not less than five), a single volume is 300-500 ml. It is recommended to put droppers every other day or every day.
All of these drugs belong to the category of a wide spectrum of effectiveness, are excreted in the urine, while disinfecting the ways in which the drug leaves the body. It is known that taking this kind of medication can provoke dyspepsia, allergies. One of the important advantages is the very slow microflora acquiring resistance to all nitrofuran derivatives. In addition to antiseptic, such drugs have chemotherapeutic properties.
Technical aspects
Briefly, the mechanism of action of nitrofuran derivatives can be described as follows: the active substance inhibits the enzymes responsible for the cyclicity of tricarboxylic acids, and NADH is simultaneously blocked. Aerobic oxidative processes involving carbohydrate compounds and anaerobic are equally blocked in the microbe cell. With a small concentration of the drug in the body, a bacteriostatic effect is observed. Increasing the dose gives a bactericidal effect.
Preparations in the practice of dentists
Indications for use of nitrofuran derivatives in dental practice:
- stomatitis (ulcerative, aphthous);
- the presence of carious cavities in need of processing;
- the need for disinfection of the root canals.
The group of antimicrobial agents is effectively used in the treatment of not only caries, but also complications provoked by it. This category of drugs is used if the resistance of microscopic life forms to sulfanilamides, other antibiotic compounds, is assumed.
Dentists nitrofuran derivatives are used to disinfect oral mucosa, pockets caused by periodontal disease, cavities provoked by caries. Such treatment is necessary when detecting wounds, infectious lesions. The tool is used externally in the form of a solution with a concentration of the active component of 0.02%.
Some features
With external use, nitrofuran derivatives can provoke negative reactions, but in practice this is observed in a vanishingly small percentage of cases. Allergies are likely. When identifying a patient’s hypersensitivity to a specific medication from the group of nitrofuran derivatives, this class of drugs cannot be used.
On sale, the funds are represented not only by solutions, tablets, but also by ointment with an active substance concentration of 0.2%. All preparations are intended for storage in a place protected from sunlight and the influence of high temperatures. An aqueous solution of nitrofuran derivatives retains its antiseptic qualities for a very long time period.
Quality control
Currently, the problem of counterfeiting drugs is quite acute, this also applies to popular antimicrobial compounds. To identify authenticity, it is necessary to make a series of reactions, following the results. Classical results are known for this group when interacting with different reagents. There are also specific methods for identifying quality for individual drugs.
To prove the authenticity of derivatives of 5-nitrofuran, the result of the reaction with the participation of an alkali solution is determined. This method belongs to the general group and is considered basic. As a rule, the mixture is painted in red, somewhat less often - in red with an orange tint. The nature and intensity of the color is determined by the substituents present in the furan core. It is known that a number of drugs give a shade change only at a very high alkaline rate, others can show a reaction when the temperature rises, and others can decrease.
An alternative general group approach is a chemical reaction involving an alkaline solution, which should lead to the release of ammonia. To do this, increase the temperature and use zinc dust, treating it with samples of drugs.
Private methods
The most widely applicable method is to create a solution of water with heavy metal salts. Complex compounds have a specific color, which changes during the course of the reaction. Furacilin in combination with a ten percent copper sulfate solution will produce a dark red precipitate, furadonin will show a brown precipitation, and furazolidone a green precipitate.
Alkaline alcohol solutions created using organic solvents can be used to identify authenticity (a fairly wide range of compounds is allowed). Most often, as solvents are:
- dimethylformamide;
- acetone.
All nitrofuran derivatives in such substances dissolve quickly and well, and the shade changes for each drug individually. Color saturation and reaction rate depend on the concentration of the alkaline compound being tested.
Medicines: how did they appear?
Currently, the classification of nitrofuran derivatives is based on the effectiveness of these agents; they distinguish well and poorly absorbed drugs from the gastrointestinal tract, as well as combined ones, in which nitrofuran-based components are included as one of the elements of a complex system. But this was far from always. The first synthetic developments, as is known from official documentation, appeared back in the nineteenth century, when organic chemistry was just becoming, but only in the second half of the last century the idea was developed to such an extent that it became possible to create effective drugs. This was largely promoted by Butlerov's theory, on the basis of which it was possible to formulate heterocycles with five elements. At this moment, all the prerequisites for working with furan compounds appeared.
The first successful synthesis of furan compounds was officially recorded in 1818, when work was done on mucus acid. A by-product of the reaction in liquid form was obtained, recorded, but not investigated, so the discovery of furan at that moment did not take place - humanity waited even more than half a century. In 1832, Dobereiner rather accidentally discovered furfural, trying using sugar, starch to make formic acid. Manganese dioxide, sulfuric acid took part in the reaction. In 1840, furfural was reopened. This time, the reaction was carried out on oatmeal, which was treated with the same sulfuric acid. The second attempt to isolate that substance made it possible to obtain sufficient volumes so that scientific research could begin, and it was then that Stanhous formulated an empirical formula, and was also able to discover the key properties of a substance new to chemists.
Terminology and History
In 1845, furfural was officially obtained from bran, and the name used at the moment was assigned to the new compound. It is formed from the Latin words "bran", "oil" and is intended to reflect the method of manufacture, special external properties. Furfurol - a word from which the terms "furan", "furfuran" and other derivatives came from.
Chemists continued experiments to identify what new compounds could be obtained from. It was possible to produce in laboratory conditions aldehyde derivatives with the participation of ammonia. They received the names "furfurin", "furfuramide." In 1870, scientists again repeated the experience of 1818, which allowed the discovery of furan. Seven years later, Bayer developed his cyclic formulas of furan.
Physics and Chemistry: Properties of Active Ingredients
Furan is a powder formed by colorless crystals. It melts when heated to 85 degrees Celsius, boils at 32 degrees. This is a pronounced acidophobia, when interacting with sulfuric acid in an increased concentration, a polymerization reaction is observed. If the acid is used in dilute form, the furan ring cleaves, resulting in the formation of 1,4-dicarbonyl compounds. The substance is prone to electrophilic substitution. Experiments have shown that furan enters into such reactions even easier and simpler than benzene.
Furan production is currently based on furfural synthesis. This compound can be obtained from fairly affordable products - waste agricultural activity. A classic source is sunflower husk or corn cobs.
What does it look like?
Normally, nitrofuran derivatives are powders created by crystal elements. They have no taste or are slightly bitter. Shades are yellowish, determined by the specificity of the side chain. Some compounds are light yellow or even orange, while others are browned with a touch of yellow. Mostly they are poorly soluble in water, but this ability can be increased by heating the mixture.
Nitrofuran derivatives are known to be highly soluble in alcohol. You can use a number of other organic substances, including dimethylformamide, propylene glycol. Medicines are characterized by increased sensitivity to sunlight, so even aqueous, alcoholic (and other) solutions of drugs should be hidden from daylight. An extremely negative effect is observed from the side of ultraviolet radiation - the molecule is destroyed almost instantly. This imposes restrictions on storage options: apply strictly glass dark containers.
"Furagin": application features
This drug can be safely ranked as the most popular nitrofuran derivative in our time. This is largely due to the possibility of combination with other antimicrobial medicines. The tool shows a pronounced effect with invasion:
- staphylococci;
- Klebsiella;
- shigella.
The active substance causes irreparable damage to the bacterial protein, due to which DNA molecules cannot be produced, respiratory processes are disturbed. Under the influence of such a reaction, the microbe that triggered the infection cannot produce the same amount of toxins as a healthy cell, which quickly leads to an improvement in well-being. Doctors pay attention: it is unacceptable to stop treatment earlier than the course recommended by the doctor ends, as well-being is not an indicator of the elimination of pathogenic microflora.