Buy Doxycycline Online
Doxycycline belongs to the antibiotics tested by time. It was synthesized in the early 60-ies of the last century, scientists of the American pharmaceutical giant Pfizer. The drug has been clinically studied and manufactured under the trade name Tetracycline.
A little later, the World Health Organization including doxycycline in the list of the most important medicines, necessary for human health.
It would seem that the development of the pharmaceutical industry and the production of new broad-spectrum antibiotics leaves no chance for the survival of such "old men," as Doxycycline. However, it is not. And the fact that the drug actually found my niche - it is an indisputable fact.
What is this antibiotic secured such a long life? What side effects should be afraid of? In this article we try to understand the properties of Doxycycline.
Structure and Composition
Doxycycline - a semi-synthetic antibacterial agent of the tetracycline group. Activity against microorganisms and chemical resistance have doxycycline derivatives: monohydrate hydrochloride and calcium salt. These three compounds are used as active ingredients.
Doxycycline is available in oral capsules and tablets of Doxycycline 100 and Doxycycline 200 mg. Parenterally, i.e. intramuscularly or intravenously this antibiotic is not applicable.
Mode of Action and Spectrum of Activity Doxycycline
Doxycycline has a marked bacteriostatic effect, inhibiting protein synthesis in a cell of a pathogenic microorganism. An important advantage is the ability of the drug to penetrate the bacterial cell wall. With this Doxycycline and has antibacterial effect against intracellular microorganisms.
The spectrum of pharmacological activity is quite impressive and includes many pathogens.
Doxycycline is active against Gram-negative bacteria, which are usually associated with intestinal infections. This group includes Campylobacter, enterobacteria, intestinal and Haemophilus influenzae, Klebsiella, gonorrhea, shigella, vibrio cholerae and other microorganisms.
A distinctive feature of the tetracycline antibiotics, including doxycycline, - low activity against most gram-positive bacteria. This explains the lack of effectiveness of tetracycline antibiotics for respiratory infections.
Almost the only Gram-positive microorganisms, which is sensitive to doxycycline, - Streptococcus pneumoniae, the most common causative agent of pneumonia.
Doxycycline has a bactericidal effect against anaerobic pathogens, which include Propionibacterium acnes. These bacteria associated with acne.
The antibiotic is effective and in infections caused by Chlamydia Chlamydophila psittaci and Chlamydia trachomatis, Mycoplasma Mycoplasma pneumoniae, treponema and ureaplasma.
Note that there is evidence Doxycycline activity against asexual erythrocytic forms of Plasmodium falciparum. At the same time the exact mechanism of action has not been established.
The drug is completely ineffective in infections caused by Proteus, Pseudomonas aeruginosa, and fungi.
Doxycycline Among other Tetracyclines
Compared with other tetracyclines Doxycycline has a number of advantages:
- Antibiotic hardly inhibits the normal intestinal microflora.
Because of this medication is rarely accompanied by diarrhea;
- More fully absorbed.
The rest of the tetracycline antibiotics have an order of magnitude lower bioavailability;
- Long-term effect.
Half-life of the drug long enough (up to 10 hours), so it can be taken only twice a day.
It should be noted that among all the tetracycline group means there is cross-resistance. That is, if tetracycline or metatsiklin had no effect, then the effect of Doxycycline wait, alas, is not necessary. The same resistance exists between doxycycline and penicillin antibiotics.
Pharmacokinetics Doxycycline: features distribution
Doxycycline, like most other tetracycline antibiotics, easily absorbed into the bloodstream and binds to plasma proteins. The drug has a very high bioavailability: the blood flows more than 90% (according to some estimates is almost 100%) of the active substance.
After receiving 200 mg Doxycycline maximum level within two hours of blood is achieved. Therapeutic concentrations detected in tissues and organs within 35-40 minutes after oral administration.
In animal experiments, it is proved that the drug penetrates the placental barrier and therefore to blood and fetal tissue. Furthermore, excellent antibiotic and falls into breast milk.
I would like to add that during long-term treatment of the drug can be cumulated. By this is not always and not everyone understood the term lies the dangerous feature of the substance or quantitatively accumulate in the tissues, or accumulating effect.
In the case of Doxycycline often occurs functional cumulation. It is expressed in the fact that some patients with repeated use of the drug accumulation effect occurs. Cumulation usually recorded in patients with severe hepatic impairment, but the toxic effect of the antibiotic still has not.
To clearly negative pharmacokinetic properties we refer Doxycycline and its ability to react with a known chelator contained in bones and teeth - calcium. Thus antibiotic forms stable complexes with macroelement. This chemical reaction is accompanied by unpleasant side effects, which we will certainly consider later.
Antibiotic: Trust - Doctors!
Experts recommend taking doxycycline and other antibacterial agents after the identification of the causative agent and determination of individual sensitivity. These measures possible to reduce the development of drug-resistant bacteria.
However, in practice, the selection of antibiotic often done empirically. In most cases, antibacterial agents administered "by eye" on the basis of the clinical manifestations of the disease. With this task the strength to cope only a qualified doctor or clinical pharmacist.
Stressing the importance of consulting a specialist, I would like once again to warn patients not self-medicate with antibiotics! This can be costly too. Long-term effects of incorrect antibiotic therapy may come back to haunt many years later.
Perhaps you will be faced with a situation where the doctors in the treatment of any infection simply powerless to dissolve hands, and not being able to choose an effective antibiotic. And the reason for it - persistence (addictive) bacteria, which occurred due to the self "treatment" antibacterial agents.
To avoid this situation in the future, we must remember that despite the theoretical possibility of a free purchase Doxycycline in our pharmacies, in any case should not take the drug without a doctor's prescription.
Doxycycline - Indications for Use
Indications Doxycycline based on the spectrum of activity. Doctors do not usually prescribe tetracycline in catarrhal infections - because these diseases are caused most often staphylococci and streptococci. But the drug is widely used in the rare infections, as well as diseases, sexually transmitted diseases.
The main diseases for which prescribe Doxycycline include respiratory tract infections (pneumonia and bronchitis in adults and children) caused by Mycoplasma pneumoniae, Chlamydia trachomatis, and Streptococcus pneumoniae.
In most cases of bronchitis and pneumonia before prescribing Doxycycline spend pathogen identification. This is necessary in order to prevent infection by staphylococcus and streptococcus, which also often cause pneumonia.
Doxycycline is widely used in diseases, sexually transmitted diseases: chlamydia, gonorrhea, mycoplasmosis, ureaplasmosis and even syphilis. Doxycycline copes with uncomplicated urethritis (inflammation of the urethra), cervicitis (inflammation of the cervix) and proctitis (inflammation of the rectum) associated with Chlamydia and Mycoplasma infection.
Although chlamydia sensitivity to doxycycline, is not always possible to achieve their elimination as monotherapy. In practice, treatment regimens include chlamydia or more drugs (tetracyclines and macrolides), or shock doses of macrolides, particularly Sumamed.
Doxycycline - one of the most effective antibacterial agents in ureaplasmosis. The antibiotic is used as a first-line at NGU caused by Ureaplasma urealyticum (ureaplasma).
Doxycycline is prescribed and when infected by Gram-negative bacteria, including the chancroid, plague, tularemia, Campylobacter infection of the fetus, which is Campylobacter fetus. Treatment includes a combination of brucellosis receiving doxycycline and streptomycin.
It remains to add that Doxycycline is also used for prevention of malaria, associated with Plasmodium falciparum. The drug is prescribed for travelers to endemic areas are in a short time (up to 4 months).
Doxycycline is an Alternative to Penicillin Antibiotics
If the patient has an allergy to penicillin antibiotics, Doxycycline is the drug of choice (second-line) for the treatment of uncomplicated gonorrhea caused by Neisseria gonorrhoeae, syphilis (pathogen - pale treponema), infectious diseases caused by clostridia.
Doxycycline also used as an additional agent for the treatment of acute intestinal amebiasis - very unpleasant intestinal infection.
Acne and Rosacea: Doxycycline for Acne
It deserves separate words antibiotic activity against microorganisms causing skin diseases. Because of these qualities it is used for the oral treatment of acne (acne), and rosacea. Simply put, Doxycycline - one of the effective drugs that help get rid of acne.
But do not forget that the treatment of these diseases should be dealt with dermatologists. Treatment of acne and rosacea - a complex and lengthy process. The treatment regimen includes far more than one vehicle, and a course of therapy may last for several months. Therefore, we must have patience, and most importantly - to find their dermatologist and not to self-medicate.
When no Laboratory Diagnosis can Not do
Scientists have found that many strains of Gram-negative bacteria may be sensitive to doxycycline. Therefore, the detection of these pathogens before prescribing an antibiotic is important to conduct an analysis on individual sensitivity.
To doxycycline may be resistant coliform bacteria, pathogens of acute intestinal infections, enterobacteria Enterobacter aerogenes, Shigella, Haemophilus and Klebsiella.
Note that the last two of the pathogen - Haemophilus influenzae and Klebsiella - associated with respiratory airways infections.
The Standard Dosage of Doxycycline
The Dose for Adults
Immediately, we note that the usual dose and frequency of administration of doxycycline differs from other antibiotics of the tetracycline group.
For adults, the usual dose of oral doxycycline is 200 mg on the first day of treatment, divided into two doses (every 12 hours). Thereafter, the dosage is reduced to 100 mg once a day.
For treatment of more severe infections it is recommended that you take 100 mg of doxycycline twice a day during the entire course of therapy.
Duration of treatment is determined individually. Note that in the treatment of streptococcal infections treatment should be not less than 10 days.
We would like to say about inhalational anthrax therapy. To this end, it recommends taking doxycycline 100 mg twice a day for at least 60 days.
The Dose for Children
The instructions for use Doxycycline indicated that children over 8 years old (weight 45 kg) are advised to take 4 mg per kilogram of body weight on the first day of treatment, divided into two steps. In the second and subsequent days of dosing must be halved (2 mg). Multiplicity of application - once a day.
This is not quite a standard treatment regimen is explained quite simply. At the beginning of antibiotic therapy for harmful microorganisms applied sudden and resounding hit a double dose of Doxycycline. After that, the weakened and buckled pathogenic bacteria and perfectly respond to low doses of antibiotics.
Dosage Genital Infections
Doxycycline High activity against Neisseria gonorrhoeae and intracellular pathogens determines the effectiveness of the drug in STDs - diseases that are sexually transmitted.
According to the instructions for Doxycycline standard treatment regimens depend on the disease.
In uncomplicated gonococcal infections (except anorectal infection in men) should take 100 mg twice a day for a week. If gonococcal and chlamydial acute orchiepididymitis (inflammation of the testis and epididymis) take Doxycycline 100 mg twice a day for at least 10 days.
In uncomplicated urethritis, cervicitis and proctitis associated with Chlamydia trachomatis, is also recommended to take 100 mg twice a day. The course of treatment - a week.
It must be emphasized that we are talking about uncomplicated forms that develop in the early stages of chlamydia. Recall that insidiousness Chlamydia trachomatis is the absence of clinical symptoms in the early stages of the disease. Therefore, chlamydia is diagnosed much later than we would like - usually already in the chronic stage. And, accordingly, the treatment regimen is not so simple, and therapy is not one week, and three and even more.
In early syphilis drug is indicated for patients who have an allergic reaction to penicillin. Doxycycline taking 200 mg, divided into two stages, for two weeks.
When syphilis for longer than one year, the dosage is 200 mg for 4 weeks.
Malaria Prevention: How to Take the Medicine?
For malaria prophylaxis recommended according to the instructions Doxycycline dose for adults is 100 mg per day.
Children 8 years of age should be about 2 mg per kilogram body weight once a day.
Prevention should start 1-2 days before the intended trip to malarious area. Take Doxycycline need on a daily basis and during the journey, and for an additional 4 weeks after return.
If you are going to travel the country, epidemicity malaria, it should be remembered that no modern medicines, including doxycycline, does not guarantee complete protection against malaria. And doctors openly admit it.
Even taking an antibiotic, do not forget about protective measures. Use mosquito nets, protect exposed areas of the body at night, use repellent - these measures are no less important than taking Doxycycline.
Contraindications: When the Antibiotic is Banned?
Let's face it: doxycycline - an antibiotic is not the safest. Among the contraindications to its use:
• Individual sensitivity to tetracycline antibiotics;
• Severe hepatic impairment;
• Pregnancy and lactation;
• Children's age (up to 8 years).
- Limiting the age due to the fact that the drug forms insoluble complexes with the calcium of the teeth and bone tissue. Therefore, the purpose of this antibiotic in the growth period of the teeth can cause a persistent discoloration of tooth enamel.
- Note that the range of Doxycycline Calcium has a brownish tint. Consequently, young children are taking tetracycline antibiotics have the potential to lose a snow-white smile.
• Porphyria - a hereditary pathology that manifests photodermatosis.
Doxycycline and Pregnancy: Be Careful!
Doxycycline belongs to the drugs category D. This means that there is a theoretical possibility of teratogenicity anitibiotika.
At the same time there had been no adequate and well-controlled studies on the use of doxycycline in pregnant women. In most works, studying the experience of using Doxycycline, it was informed of the absence of effect of the drug on the fetus when used in the short-term 1 trimester of pregnancy. The impact of long-term treatment has not been studied.
TIS - Teratogenic Information System - published data suggest that therapeutic doses of doxycycline have no teratogenic risk. But obviously not enough evidence-based information makes it impossible to completely deny the existence of a teratogenic effect.
Given these, frankly, contradictory data, most experts refrain from the use of Doxycycline in 1 trimester. A drug altogether officially contraindicated in 2 and 3 trimester of pregnancy.
Doxycycline: Special Instructions
Tetracycline antibiotics have a number of not the most positive qualities that can influence our body. However, we are able to neutralize the negative effect of Doxycycline, if we follow the rules of use of this drug.
Experts warn that Doxycycline is able to irritate the esophagus. To avoid the formation of ulcerative lesions during treatment drink as much liquid as possible.
Tetracycline antibiotics, particularly doxycycline, have photosensitizing effect, ie increase the sensitivity of the body to the action of ultraviolet light. Therefore, during treatment to avoid sun exposure and use sunscreen cosmetics.
And the Last. Doxycycline irreversibly binds to calcium. In this connection, experts advise for three hours before and after administration of drinking milk, yogurt and other dairy products.