Pharmacological action of Doxycycline
The active component of Doxycycline has a bacteriostatic effect against many gram-positive and gram-negative microorganisms.
Penetrating inside the cell, the drug affects intracellular pathogens. The medicine is active against most pathogens of serious infectious diseases - tularemia, plague and anthrax microbes, as well as Brucella, Legionella, Rickettsia, Vibrio cholerae and glanders pathogens. In addition, the administration of Doxycycline for ureaplasma and chlamydia is effective.
Unlike other antibiotics, Doxycycline, according to the instructions, inhibits the intestinal flora to a lesser extent, and is also characterized by a longer duration of therapeutic action.
Contraindications
Doxycycline is not prescribed for tonsillitis if there are contraindications. Taking this drug is strictly prohibited for the following diseases and conditions:
- In case of intolerance to individual components that are included in the medicinal product.
- With a low level of leukocytes in the blood.
- In case of renal or liver failure.
- During pregnancy and lactation period.
- If the patient weighs less than 45 kg.
It is strictly forbidden to prescribe the drug to children under 9 years of age, as there is a high probability of developing side effects..
To treat sore throat in children, doctors try to select the latest generation of antibiotics that have few side effects.
Indications for use of Doxycycline
Doxycycline, according to the instructions, is prescribed for the treatment of many infectious and inflammatory diseases:
- ENT organs – tonsillitis, sinusitis, otitis;
- Respiratory tract – lung abscess, pharyngitis, tracheitis, bronchitis (acute and chronic), lobar pneumonia, bronchopneumonia, pleural empyema;
- Biliary tract and gastrointestinal tract - cholangitis, cholecystitis, bacterial dysentery, gastroenterocolitis, traveler's diarrhea;
- Genitourinary system – endometritis, pyelonephritis, cystitis, urethritis, prostatitis, urethrocystitis, gonorrhea, urogenital mycoplasmosis, endocervicitis, acute orchiepididymitis;
- Skin and soft tissues - furunculosis, abscesses, infected burns, wounds.
Also, the use of Doxycycline is effective in the treatment of:
- Syphilis;
- Infectious eye diseases;
- Chlamydia of various localizations, including proctitis and prostatitis;
- Yaws;
- Actinomycosis;
- Rocky Mountain Spotted Fever;
- Q fever;
- Cholera;
- Typhoid, including typhoid and tick-borne;
- Malaria.
Recently, ureaplasma has often shown resistance to Doxycycline, but in some cases the use of the drug is justified.
In addition, Doxycycline, according to the instructions, is prescribed as part of combination therapy for leptospirosis, brucellosis, peritonitis, trachoma, psittacosis, psittacosis, whooping cough, sepsis, osteomyelitis, subacute septic endocarditis, as well as for the prevention of postoperative purulent complications.
Manufacturer of Doxycycline®
The semi-synthetic antibiotic was discovered in the 60s of the last century. The synthesis was carried out by the American company Pfizer®, which for the first time released a new drug onto the pharmaceutical market, giving it the name Vibramycin®. Currently, other producing countries are on the market: Russia, Germany, Jordan, Cyprus, Canada, the Netherlands, etc.
All of them take as a basis the main component of the drug - Doxycycline®, and by adding auxiliary components they form the final product. After confirming its safety, the antibiotic is supplied to the markets of countries that cooperate with the companies.
Directions for use and dosage of Doxycycline
Doxycycline is administered intravenously in the treatment of severe forms of purulent-septic diseases, as well as in cases of difficulty in taking the drug orally.
In the acute stage of pelvic inflammatory diseases in women, Doxycycline is administered 0.1 g every 12 hours, after which therapy is continued with tablets for two weeks.
The course dose of Doxycycline depends on the disease and its course. As a rule, they prescribe:
- In the treatment of acute uncomplicated urethritis - 0.5 g for a week;
- For uncomplicated infections of the urethra - 0.1 g twice a day for a week;
- When treating syphilis - 0.3 g daily for 10 days;
- For malaria - 0.2 g per day for a week;
- For infections of the male genital organs - for a month, twice a day, 0.1 g;
- When treating leptospirosis - 0.1 g twice a day for a week;
- For the treatment and prevention of traveler's diarrhea - 0.2 g for no longer than three weeks;
- When treating acne - up to 12 weeks, 0.1 g per day.
When treating ureaplasma, Doxycycline is prescribed by a doctor individually.
In pediatrics, Doxycycline is usually prescribed at a daily dose of 4 mg per 1 kg of body weight on the first day of therapy, after which the dose is halved.
Against the background of severe liver failure, reduced doses of Doxycycline should be used.
Summary
Doctors prescribe doxycycline to treat serious bacterial infections. People also use doxycycline to treat acne and rosacea.
Before taking doxycycline, patients should tell their doctor about any other drugs they are taking. Doxycycline may not be suitable for everyone, especially during pregnancy. The doctor must weigh the benefits of treatment against the possible risks.
Children 8 years of age and younger can take doxycycline, but they are at risk for permanent yellowing of their teeth.
Another article on the topic: Is it possible to drink alcohol while taking antibiotics?
Side effects of Doxycycline
Typically, Doxycycline, according to reviews, when used in therapeutic dosages does not lead to the development of side effects. However, in some cases, the medication in all dosage forms can cause disorders in many body systems in the form of:
- Benign increase in intracranial pressure, which is accompanied by loss of appetite, headache, vomiting, swelling of the optic disc (nervous system);
- Neutropenia, thrombocytopenia, hemolytic anemia, eosinophilia (hematopoietic organs);
- Nausea, constipation or diarrhea, glossitis, dysphagia, esophagitis (including erosive), gastritis, enterocolitis (digestive system).
Most often, when using Doxycycline, according to reviews, allergic reactions develop such as skin itching, drug-induced lupus erythematosus, maculopapular rash, angioedema, skin hyperemia and anaphylactoid reactions.
In addition, in some cases, during Doxycycline therapy, according to reviews, the following may be observed:
- Superinfection;
- Photosensitivity;
- Inflammation in the anogenital area;
- Persistent discoloration of tooth enamel;
- Candidiasis – glossitis, vaginitis, proctitis, stomatitis;
- Dysbacteriosis.
Since Doxycycline can lead to the development of photosensitivity, time spent in light should be limited during therapy and for a week after its completion.
General characteristics of the drug
Doxycycline is an antibacterial drug of the tetracycline group, which has a wide spectrum of action. This semi-synthetic antibiotic prevents the proliferation of pathogenic microbes, thereby accelerating recovery .
Many pathogens of aerobic and anaerobic infections are sensitive to Doxycycline. Streptococci, staphylococci, salmonella, and E. coli are susceptible to the drug. This drug can treat cholera, plague, anthrax and other dangerous infections. This antibiotic is especially often prescribed if the causative agent of the disease remains unknown.
The antibiotic is almost completely absorbed in the stomach, reaching the maximum permissible concentration in the blood in just 2 hours. Eating does not affect the degree of absorption at all. The drug has a prolonged effect, so it can be taken only once a day.
Doxycycline is available in different dosage forms. The doctor may prescribe:
- Powder for the preparation of an isotonic solution and subsequent intravenous administration.
- In capsules and tablets.
The attending physician determines which form of the drug to use in a particular case. This depends on the age of the patient and the severity of the disease.
Doxycycline has no effect on fungi and viruses at all, so it is not advisable to prescribe it for such pathologies.
Doxycycline drug interactions
When using Doxycycline, dose adjustment of indirect anticoagulants is required, which is associated with suppression of intestinal microflora.
The effectiveness of penicillins and cephalosporins is reduced when used simultaneously with Doxycycline. The medicine also reduces the reliability of contraception, and while taking estrogen-containing oral contraceptives, an increase in the frequency of breakthrough bleeding is observed.
The therapeutic effect of Doxycycline is reduced when used simultaneously with carbamazepine, ethanol, rifampicin, barbiturates, phenytoin and other stimulants of microsomal oxidation.
Additional instructions
To prevent photosensitivity, ultraviolet rays should be avoided during and for five days after the course. Monitoring of hematopoietic organs and liver is required, as well as serological analysis for four months. The use of doxycycline with medications containing ions (for example, antacids or calcium supplements) is not recommended. Together they form inactive chelates - the absorption of the antibiotic decreases.
The use of this antibiotic with agents that promote the induction of microsomal liver enzymes (barbiturates, ethanol, carbamazepines, rifampicin, phenytoins) reduces the bacteriostatic effect. For the same reason, it is not combined with bactericidal antibiotics (bacteriostatic antagonists, for example, cephalosporins).
It is important to consider how doxycycline is combined with other drugs
Combination with penicillins and cephalosporins should be avoided.
The antibiotic suppresses enteral microflora. Microorganisms promote the synthesis of vitamin K, and dysbiosis can lead to a decrease in the synthesis of K-dependent blood coagulation factors, therefore monitoring of coagulation characteristics and their correction with the help of anticoagulants (indirect, for example, warfarin) is necessary.
The combination of retinol and doxycycline increases intracranial pressure, and the combination with methoxyflurane (narcotic and hypnotic) leads to nephrotoxicity (damage to the functional units of the kidneys).
The combination of doxycycline and some other substances can lead to health problems
Pharmacodynamics
Active against gram-positive cocci (S.aureus), coagulase-negative staphylococci, streptococci (S.pneumoniae, S.pyogenes - group A, S.agalactiae - group B, S.viridans, strains of A.israelii, B.anthracis, L. monocytogenes ), gram-negative cocci (N.meningitidis, N.gonorrhoeae, B.catarrhalis), rods (Bordetella, Brucella spp., Calymmatobacterium granulomatis, Campylobacter spp., F.tularensis, H.influenzae, H.ducreyi, Legionella, P.multocida , Yersinia spp.), Vibrionaceae strains (V.cholerae, V.parahaemolyticus), other microorganisms (Helicobacter pylori, Chlamydia spp., Rickettsia spp., Coxiella spp.), spirochetes (Borrelia burgdorferi, Leptospira interrogans, Treponema pallidum), Mycobacterium spp., Mycoplasma pneumoniae, Ureaplasma urealyticum, as well as protozoa (Plasmodium falciparum, Entamoeba histolytica).
