Clinical data | |
---|---|
Pronunciation | /ˌdɒksɪˈsaɪkliːn/ DOKS-iss-EYE-kleen |
Trade names | Doxy, Doryx, Vibramycin, others |
AHFS/Drugs.com | Monograph |
MedlinePlus | a682063 |
License data |
|
Pregnancy category |
|
Routes of administration | By mouth, intravenous [1] |
ATC code | |
Legal status | |
Legal status | |
Pharmacokinetic data | |
Bioavailability | ~100% |
Protein binding | 80–90% |
Metabolism | Negligible |
Elimination half-life | 10–22 hours |
Excretion | Mainly feces, 40% urine |
Identifiers | |
| |
CAS Number | |
PubChem CID | |
DrugBank | |
ChemSpider | |
UNII | |
KEGG | |
ChEBI | |
ChEMBL | |
CompTox Dashboard (EPA) | |
ECHA InfoCard | 100.008.429 |
Chemical and physical data | |
Formula | C22H24N2O8 |
Molar mass | 444.440 g·mol−1 |
3D model (JSmol) | |
| |
| |
(what is this?) (verify) |
Doxycycline is a broad-spectrum antibiotic of the tetracycline class used in the treatment of infections caused by bacteria and certain parasites. [1] It is used to treat bacterial pneumonia, acne, chlamydia infections, Lyme disease, cholera, typhus, and syphilis. [1] It is also used to prevent malaria. [2] [3] Doxycycline may be taken by mouth or by injection into a vein. [1]
Common side effects include diarrhea, nausea, vomiting, abdominal pain, and an increased risk of sunburn. [1] Use during pregnancy is not recommended. [1] Like other agents of the tetracycline class, it either slows or kills bacteria by inhibiting protein production. [1] [4] It kills malaria by targeting a plastid organelle, the apicoplast. [5] [6]
Doxycycline was patented in 1957 and came into commercial use in 1967. [7] [8] It is on the World Health Organization's List of Essential Medicines. [9] Doxycycline is available as a generic medicine. [1] [10] In 2021, it was the 82nd most commonly prescribed medication in the United States, with more than 8 million prescriptions. [11] [12]
In addition to the general indications for all members of the tetracycline antibiotics group, doxycycline is frequently used to treat Lyme disease, chronic prostatitis, sinusitis, pelvic inflammatory disease, [13] [14] severe acne, rosacea, [15] [16] [17] and rickettsial infections. [18]
In Canada, in 2004, doxycycline was considered a first-line treatment for chlamydia and non-gonococcal urethritis and with cefixime for uncomplicated gonorrhea. [19]
Doxycycline is a broad-spectrum antibiotic that is employed in the treatment of numerous bacterial infections. It is effective against bacteria such as Moraxella catarrhalis , Brucella melitensis , Chlamydia pneumoniae , and Mycoplasma pneumoniae . Additionally, doxycycline is used in the prevention and treatment of serious conditions like anthrax, leptospirosis, bubonic plague, and Lyme disease. However, some bacteria, including Haemophilus spp., Mycoplasma hominis , and Pseudomonas aeruginosa , have shown resistance to doxycycline. [20] [21] It is also effective against Yersinia pestis (the infectious agent of bubonic plague), and is prescribed for the treatment of Lyme disease, [22] [23] [24] [25] ehrlichiosis, [26] [27] and Rocky Mountain spotted fever. [28]
Specifically, doxycycline is indicated for treatment of the following diseases: [28] [29]
When bacteriologic testing indicates appropriate susceptibility to the drug, doxycycline may be used to treat these infections caused by Gram-negative bacteria: [28] [29]
Some Gram-positive bacteria have developed resistance to doxycycline. Up to 44% of Streptococcus pyogenes and up to 74% of S. faecalis specimens have developed resistance to the tetracycline group of antibiotics. Up to 57% of P. acnes strains developed resistance to doxycycline. [38] When bacteriologic testing indicates appropriate susceptibility to the drug, doxycycline may be used to treat these infections caused by Gram-positive bacteria: [28] [29]
When penicillin is contraindicated, doxycycline can be used to treat: [28] [29]
Doxycycline may also be used as adjunctive therapy for severe acne. [39] [28] [29]
Subantimicrobial-dose doxycycline (SDD) is widely used as an adjunctive treatment to scaling and root planing for periodontitis. Significant differences were observed for all investigated clinical parameters of periodontitis in favor of the scaling and root planing + SDD group where SDD dosage regimens is 20 mg twice daily for three months in a meta-analysis published in 2011. [40] SDD is also used to treat skin conditions such as acne and rosacea, [15] [41] [42] including ocular rosacea. [43] In ocular rosacea, treatment period is 2 to 3 months. After discontinuation of doxycycline, recurrences may occur within three months; therefore, many studies recommend either slow tapering or treatment with a lower dose over a longer period of time. [43]
Doxycycline is used as an adjunctive therapy for acute intestinal amebiasis. [44]
Doxycycline is also used as an adjunctive therapy for chancroid. [44]
As well as being used to treat some sexually transmitted infections, doxycycline can also be used as a preventative measure, i.e. as post-exposure prophylaxis (often referred to as "doxyPEP"). Three randomised controlled trials have demonstrated efficacy in the prevention of syphilis and chlamydia, and to a lesser extent gonorrhoea, in gay and bisexual men, as well as trans women. [45] A study conducted with heterosexual women in Kenya was unsuccessful, probably due to poor adherence. [46] Appropriate use of doxycycline in this way is supported by guidelines from the US Centers for Disease Control and Prevention (CDC) [47] and the Australasian Society for HIV Medicine. [48] The rapid uptake of "doxyPEP" among gay and bisexual men in San Francisco is credited with reducing the incidence of chlamydia and syphilis in 2023. [49]
The first-line treatment for brucellosis is a combination of doxycycline and streptomycin and the second-line is a combination of doxycycline and rifampicin (rifampin). [50]
Doxycycline is active against the erythrocytic stages of Plasmodium falciparum but not against the gametocytes of P. falciparum. [51] It is used to prevent malaria. [52] It is not recommended alone for initial treatment of malaria, even when the parasite is doxycycline-sensitive, because the antimalarial effect of doxycycline is delayed. [53]
Doxycycline blocks protein production in apicoplast (an organelle) of P. falciparum—such blocking leads to two main effects: it disrupts the parasite's ability to produce fatty acids, which are essential for its growth, and it impairs the production of heme, a cofactor. These effects occur late in the parasite's life cycle when it is in the blood stage, causing the symptoms of malaria. [54] By blocking important processes in the parasite, doxycycline both inhibits the growth and prevents the multiplication of P. falciparum. It does not directly kill the living organisms of P. falciparum but creates conditions that prevent their growth and replication. [55]
The World Health Organization (WHO) guidelines state that the combination of doxycycline with either artesunate or quinine may be used for the treatment of uncomplicated malaria due to P. falciparum or following intravenous treatment of severe malaria. [56]
Doxycycline kills the symbiotic Wolbachia bacteria in the reproductive tracts of parasitic filarial nematodes, making the nematodes sterile, and thus reducing transmission of diseases such as onchocerciasis and elephantiasis. [57] Field trials in 2005 showed an eight-week course of doxycycline almost eliminates the release of microfilariae. [58]
Doxycycline has been used successfully to treat sexually transmitted, respiratory, and ophthalmic infections. Representative pathogenic genera include Chlamydia, Streptococcus, Ureaplasma, Mycoplasma , and others. The following represents minimum inhibitory concentration susceptibility data for a few medically significant microorganisms. [59]
Doxycycline is also used for sclerotherapy in slow-flow vascular malformations, namely venous and lymphatic malformations, as well as post-operative lymphoceles. [60]
Doxycycline can be administered via oral or intravenous routes. [1]
The combination of doxycycline with dairy, antacids, calcium supplements, iron products, laxatives containing magnesium, or bile acid sequestrants is not inherently dangerous, but any of these foods and supplements may decrease absorption of doxycycline. [61] [62]
Doxycycline has a high oral bioavailability, as it is almost completely absorbed in the stomach and proximal small intestine. [15] Unlike other tetracyclines, its absorption is not significantly affected by food or dairy intake. [15] However, co-administration of dairy products reduces the serum concentration of doxycycline by 20%. [15] Doxycycline absorption is also inhibited by divalent and trivalent cations, such as iron, bismuth, aluminum, calcium and magnesium. [15] Doxycycline forms unstable complexes with metal ions in the acidic gastric environment, which dissociate in the small intestine, allowing the drug to be absorbed. However, some doxycycline remains complexed with metal ions in the duodenum, resulting in a slight decrease in absorption. [15]
Severe liver disease or concomitant use of isotretinoin or other retinoids are contraindications, as both tetracyclines and retinoids can cause intracranial hypertension (increased pressure around the brain) in rare cases. [61]
Doxycycline is categorized by the FDA as a class D drug in pregnancy. Doxycycline crosses into breastmilk. [63] Other tetracycline antibiotics are contraindicated in pregnancy and up to eight years of age, due to the potential for disrupting bone and tooth development. [64] They include a class warning about staining of teeth and decreased development of dental enamel in children exposed to tetracyclines in utero, during breastfeeding or during young childhood. [65] However, the FDA has acknowledged that the actual risk of dental staining of primary teeth is undetermined for doxycycline specifically. The best available evidence indicates that doxycycline has little or no effect on hypoplasia of dental enamel or on staining of teeth and the CDC recommends the use of doxycycline for treatment of Q fever and also for tick-borne rickettsial diseases in young children and others advocate for its use in malaria. [66]
Adverse effects are similar to those of other members of the tetracycline antibiotic group. Doxycycline can cause gastrointestinal upset. [67] [68] Oral doxycycline can cause pill esophagitis, particularly when it is swallowed without adequate fluid, or by persons with difficulty swallowing or impaired mobility. [69] Doxycycline is less likely than other antibiotic drugs to cause Clostridium difficile colitis . [70]
An erythematous rash in sun-exposed parts of the body has been reported to occur in 7.3–21.2% of persons taking doxycycline for malaria prophylaxis. One study examined the tolerability of various malaria prophylactic regimens and found doxycycline did not cause a significantly higher percentage of all skin events (photosensitivity not specified) when compared with other antimalarials. The rash resolves upon discontinuation of the drug. [71]
Unlike some other members of the tetracycline group, it may be used in those with renal impairment. [72]
Doxycycline use has been associated with increased risk of inflammatory bowel disease. [73] In one large retrospective study, patients who were prescribed doxycycline for their acne had a 2.25-fold greater risk of developing Crohn's disease. [74]
Previously, doxycycline was believed to impair the effectiveness of many types of hormonal contraception due to CYP450 induction. Research has shown no significant loss of effectiveness in oral contraceptives while using most tetracycline antibiotics (including doxycycline), although many physicians still recommend the use of barrier contraception for people taking the drug to prevent unwanted pregnancy. [75] [72] [76]
Doxycycline, like other tetracycline antibiotics, is bacteriostatic. It works by preventing bacteria from reproducing through the inhibition of protein synthesis. [77]
Doxycycline is highly lipophilic, so it can easily enter cells, meaning the drug is easily absorbed after oral administration and has a large volume of distribution. It can also be re-absorbed in the renal tubules and gastrointestinal tract due to its high lipophilicity, giving it a long elimination half-life, and it is also prevented from accumulating in the kidneys of patients with kidney failure due to the compensatory excretion in faeces. [68] [78] Doxycycline–metal ion complexes are unstable at acid pH, therefore more doxycycline enters the duodenum for absorption than the earlier tetracycline compounds. In addition, food has less effect on absorption than on absorption of earlier drugs with doxycycline serum concentrations being reduced by about 20% by test meals compared with 50% for tetracycline. [79]
Doxycycline is a broad-spectrum bacteriostatic antibiotic. It inhibits the synthesis of bacterial proteins by binding to the 30S ribosomal subunit, which is only found in bacteria. [67] [78] This prevents the binding of transfer RNA to messenger RNA at the ribosomal subunit meaning amino acids cannot be added to polypeptide chains and new proteins cannot be made. This stops bacterial growth giving the immune system time to kill and remove the bacteria. [80]
The substance is almost completely absorbed from the upper part of the small intestine. It reaches highest concentrations in the blood plasma after one to two hours and has a high plasma protein binding rate of about 80–90%. Doxycycline penetrates into almost all tissues and body fluids. Very high concentrations are found in the gallbladder, liver, kidneys, lung, breast milk, bone and genitals; low ones in saliva, aqueous humor, cerebrospinal fluid (CSF), and especially in inflamed meninges. [61] [81] [82] By comparison, the tetracycline antibiotic minocycline penetrates significantly better into the CSF and meninges. [83]
Doxycycline metabolism is negligible. It is actively excreted into the gut (in part via the gallbladder, in part directly from blood vessels), where some of it is inactivated by forming chelates. About 40% are eliminated via the kidneys, much less in people with end-stage kidney disease. The biological half-life is 18 to 22 hours (16 ± 6 hours according to another source [81] ) in healthy people, slightly longer in those with end-stage kidney disease, and significantly longer in those with liver disease. [61] [81] [82]
Expired tetracyclines or tetracyclines allowed to stand at a pH less than 2 are reported to be nephrotoxic due to the formation of a degradation product, anhydro-4-epitetracycline [84] [85] causing Fanconi syndrome. [86] In the case of doxycycline, the absence of a hydroxyl group in C-6 prevents the formation of the nephrotoxic compound. [85] Nevertheless, tetracyclines and doxycycline itself have to be taken with caution in patients with kidney injury, as they can worsen azotemia due to catabolic effects. [86]
Doxycycline, doxycycline monohydrate and doxycycline hyclate are yellow, crystalline powders with a bitter taste. The latter smells faintly of ethanol, a 1% aqueous solution has a pH of 2–3, and the specific rotation is −110° cm3/dm·g in 0.01 N methanolic hydrochloric acid. [81]
Solubility in | Doxycycline | Doxycycline monohydrate | Doxycycline hyclate |
---|---|---|---|
Water | very slightly | very slightly | freely |
Ethanol | very slightly | very slightly | sparingly |
Aqueous acids | freely | freely | |
Alkali hydroxyde solutions | freely | freely | |
Chloroform | very slightly | practically insoluble | practically insoluble |
Diethyl ether | insoluble | practically insoluble | practically insoluble |
After penicillin revolutionized the treatment of bacterial infections in World War II, many chemical companies moved into the field of discovering antibiotics by bioprospecting. American Cyanamid was one of these, and in the late 1940s chemists there discovered chlortetracycline, the first member of the tetracycline class of antibiotics. [4] Shortly thereafter, scientists at Pfizer discovered oxytetracycline and it was brought to market. Both compounds, like penicillin, were natural products and it was commonly believed that nature had perfected them, and further chemical changes could only degrade their effectiveness. Scientists at Pfizer led by Lloyd Conover modified these compounds, which led to the invention of tetracycline itself, the first semi-synthetic antibiotic. Charlie Stephens' group at Pfizer worked on further analogs and created one with greatly improved stability and pharmacological efficacy: doxycycline. It was clinically developed in the early 1960s and approved by the FDA in 1967. [4]
As its patent grew near to expiring in the early 1970s, the patent became the subject of lawsuit between Pfizer and International Rectifier [87] that was not resolved until 1983; at the time it was the largest litigated patent case in US history. [88] Instead of a cash payment for infringement, Pfizer took the veterinary and feed-additive businesses of International Rectifier's subsidiary, Rachelle Laboratories. [88]
In January 2013, the FDA reported shortages of some, but not all, forms of doxycycline "caused by increased demand and manufacturing issues". [89] Companies involved included an unnamed major generics manufacturer that ceased production in February 2013, Teva (which ceased production in May 2013), Mylan, Actavis, and Hikma Pharmaceuticals. [90] [91] The shortage came at a particularly bad time, since there were also shortages of an alternative antibiotic, tetracycline, at the same time. [92] The market price for doxycycline dramatically increased in the United States in 2013 and early 2014 (from $20 to over $1800 for a bottle of 500 tablets), [93] [94] [95] before decreasing again. [96] [97]
Doxycycline is available worldwide under many brand names. [98] Doxycycline is available as a generic medicine. [1] [10]
Research areas on the application of doxycycline include the following medical conditions:
Some studies show doxycycline as a potential agent to possess anti-inflammatory properties acting by inhibiting proinflammatory cytokines such as interleukin-1 (IL-1), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and matrix metalloproteinases (MMPs) while increasing the production of anti-inflammatory cytokines such as interleukin-10 (IL-10). Cytokines are small proteins that are secreted by immune cells and play a key role in the immune response. Some studies suggest that doxycycline can suppress the activation of the nuclear factor-kappa B (NF-κB) pathway, which is responsible for upregulating several inflammatory mediators in various cells, including neurons; therefore, it is studied as a potential agent for treating neuroinflammation. [101] [102] [103]
A potential explanation of doxycycline's anti-inflammatory properties is its inhibition of matrix metalloproteinases (MMPs), which are a group of proteases known to regulate the turnover of extracellular matrix (ECM) and thus are suggested to be important in the process of several diseases associated with tissue remodeling and inflammation. [104] [105] [106] [107] Doxycycline has been shown to inhibit MMPs, including matrilysin (MMP7), by interacting with the structural zinc atom and/or calcium atoms within the structural metal center of the protein. [108] [109] [110]
Doxycycline is used to treat acne vulgaris and rosacea. [111] [112] [15] However, there is no clear understanding of what contributes more: the bacteriostatic properties of doxycycline, which affect bacteria (such as Propionibacterium acnes [15] ) on the surface of sebaceous glands even in lower doses called "submicrobial" [113] [114] or "subantimicrobial", [115] [116] [117] [15] or whether doxycycline's anti-inflammatory effects, which reduce inflammation in acne vulgaris and rosacea, including ocular rosacea, [43] contribute more to its therapeutic effectiveness against these skin conditions. [118] Subantimicrobial-dose doxycycline (SDD) can still have a bacteriostatic effect, especially when taken for extended periods, such as several months in treating acne and rosacea. [119] While the SDD is believed to have anti-inflammatory effects rather than solely antibacterial effects, SDD was proven to work by reducing inflammation associated with acne and rosacea. Still, the exact mechanisms have yet to be fully discovered. [120] One probable mechanism is doxycycline's ability to decrease the amount of reactive oxygen species (ROS). Inflammation in rosacea may be associated with increased production of ROS by inflammatory cells; these ROS contribute toward exacerbating symptoms. Doxycycline may reduce ROS levels and induce antioxidant activity because it directly scavenges hydroxyl radicals and singlet oxygen, helping minimize tissue damage caused by highly oxidative and inflammatory conditions. [121] Studies have shown that SDD can effectively improve acne and rosacea symptoms, [122] probably without inducing antibiotic resistance. [123]
Doxycycline's dual benefits as an antibacterial and anti-inflammatory make it a helpful treatment option for diseases involving inflammation not only of the skin, such as rosacea and acne, but also in conditions such as osteoarthritis or periodontitis. [124] Nevertheless, current results are inconclusive, and evidence of doxycycline's anti-inflammatory properties needs to be improved, considering conflicting reports from animal models so far. [125] [126] [127] Doxycycline has been studied in various immunological disorders, including rheumatoid arthritis, lupus, and periodontitis. [128] In these conditions, doxycycline has been researched to determine anti-inflammatory and immunomodulatory effects that could be beneficial in treating these conditions. However, a solid conclusion still needs to be provided. [129] [130] [131] [132]
Doxycycline is also studied for its neuroprotective properties which are associated with antioxidant, anti-apoptotic, and anti-inflammatory mechanisms. In this context, it is important to note that doxycycline is able to cross the blood-brain barrier. Several studies have shown that doxycycline inhibits dopaminergic neurodegeneration through the upregulation of axonal and synaptic proteins. [133] [134] Axonal degeneration and synaptic loss are key events at the early stages of neurodegeneration and precede neuronal death in neurodegenerative diseases, including Parkinson's disease (PD). Therefore, the regeneration of the axonal and synaptic network might be beneficial in PD. [135] It has been demonstrated that doxycycline mimics nerve growth factor (NGF) signaling in PC12 cells. However, the involvement of this mechanism in the neuroprotective effect of doxycycline is unknown. Doxycycline is also studied in reverting inflammatory changes related to depression. [116] While there is some research on the use of doxycycline for treating major depressive disorder, the results are mixed. [116] [136] [137]
After a large-scale trial showed no benefit of using doxycycline in treating COVID‑19, the UK's National Institute for Health and Care Excellence (NICE) updated its guidance to not recommend the medication for the treatment of COVID‑19. [138] [139] Doxycycline was expected to possess anti-inflammatory properties that could lessen the cytokine storm associated with a SARS-CoV-2 infection, but the trials did not demonstrate the expected benefit. [140] Researchers also believed that doxycycline possesses anti-inflammatory and immunomodulatory effects that could reduce the production of cytokines in COVID-19, but these supposed effects failed to improve the outcome of COVID-19 treatment. [141] [142]
Research on novel drug formulations for the delivery of doxycycline in wound treatment is expanding, focusing on overcoming stability limitations for long-term storage and developing consumer-friendly, parenteral antibiotic delivery systems. The most common and practical form of doxycycline delivery is through wound dressings, which have evolved from mono- to three-layered systems to maximize healing effectiveness. [143]
Research directions on the use of doxycycline in wound healing include the continuous stabilization of doxycycline, scaling up technology and industrial production, and exploring non-contact wound treatment methods like sprays and aerosols for use in emergencies and when medical care is not readily accessible. [143]
Doxycycline and other members of the tetracycline class of antibiotics are often used as research reagents in in vitro and in vivo biomedical research experiments involving bacteria as well in experiments in eukaryotic cells and organisms with inducible protein expression systems using tetracycline-controlled transcriptional activation. The mechanism of action for the antibacterial effect of tetracyclines relies on disrupting protein translation in bacteria, thereby damaging the ability of microbes to grow and repair; however protein translation is also disrupted in eukaryotic mitochondria impairing metabolism and leading to effects that can confound experimental results. [144] [145] Doxycycline is also used in "tet-on" (gene expression activated by doxycycline) and "tet-off" (gene expression inactivated by doxycycline) tetracycline-controlled transcriptional activation to regulate transgene expression in organisms and cell cultures. [146] Doxycycline is more stable than tetracycline for this purpose. [146] At subantimicrobial doses, doxycycline is an inhibitor of matrix metalloproteases, and has been used in various experimental systems for this purpose, such as for recalcitrant recurrent corneal erosions. [147]
Chlamydia, or more specifically a chlamydia infection, is a sexually transmitted infection caused by the bacterium Chlamydia trachomatis. Most people who are infected have no symptoms. When symptoms do appear they may occur only several weeks after infection; the incubation period between exposure and being able to infect others is thought to be on the order of two to six weeks. Symptoms in women may include vaginal discharge or burning with urination. Symptoms in men may include discharge from the penis, burning with urination, or pain and swelling of one or both testicles. The infection can spread to the upper genital tract in women, causing pelvic inflammatory disease, which may result in future infertility or ectopic pregnancy.
Tetracycline, sold under various brand names, is an oral antibiotic in the tetracyclines family of medications, used to treat a number of infections, including acne, cholera, brucellosis, plague, malaria, and syphilis.
Acne, also known as acne vulgaris, is a long-term skin condition that occurs when dead skin cells and oil from the skin clog hair follicles. Typical features of the condition include blackheads or whiteheads, pimples, oily skin, and possible scarring. It primarily affects skin with a relatively high number of oil glands, including the face, upper part of the chest, and back. The resulting appearance can lead to lack of confidence, anxiety, reduced self-esteem, and, in extreme cases, depression or thoughts of suicide.
Minocycline, sold under the brand name Minocin among others, is a tetracycline antibiotic medication used to treat a number of bacterial infections such as some occurring in certain forms of pneumonia. It is generally less preferred than the tetracycline doxycycline. Minocycline is also used for the treatment of acne and rheumatoid arthritis. It is taken by mouth or applied to the skin.
Lymphogranuloma venereum is a sexually transmitted infection caused by the invasive serovars L1, L2, L2a, L2b, or L3 of Chlamydia trachomatis.
Metronidazole, sold under the brand name Flagyl among others, is an antibiotic and antiprotozoal medication. It is used either alone or with other antibiotics to treat pelvic inflammatory disease, endocarditis, and bacterial vaginosis. It is effective for dracunculiasis, giardiasis, trichomoniasis, and amebiasis. It is an option for a first episode of mild-to-moderate Clostridioides difficile colitis if vancomycin or fidaxomicin is unavailable. Metronidazole is available orally, as a cream or gel, and by slow intravenous infusion.
Chlamydia trachomatis, commonly known as chlamydia, is a bacterium that causes chlamydia, which can manifest in various ways, including: trachoma, lymphogranuloma venereum, nongonococcal urethritis, cervicitis, salpingitis, pelvic inflammatory disease. C. trachomatis is the most common infectious cause of blindness and the most common sexually transmitted bacterium.
A broad-spectrum antibiotic is an antibiotic that acts on the two major bacterial groups, Gram-positive and Gram-negative, or any antibiotic that acts against a wide range of disease-causing bacteria. These medications are used when a bacterial infection is suspected but the group of bacteria is unknown or when infection with multiple groups of bacteria is suspected. This is in contrast to a narrow-spectrum antibiotic, which is effective against only a specific group of bacteria. Although powerful, broad-spectrum antibiotics pose specific risks, particularly the disruption of native, normal bacteria and the development of antimicrobial resistance. An example of a commonly used broad-spectrum antibiotic is ampicillin.
Oxytetracycline is a broad-spectrum tetracycline antibiotic, the second of the group to be discovered.
Cutibacterium acnes is the relatively slow-growing, typically aerotolerant anaerobic, gram-positive bacterium (rod) linked to the skin condition of acne; it can also cause chronic blepharitis and endophthalmitis, the latter particularly following intraocular surgery. Its genome has been sequenced and a study has shown several genes can generate enzymes for degrading skin and proteins that may be immunogenic.
Clindamycin is a lincosamide antibiotic medication used for the treatment of a number of bacterial infections, including osteomyelitis (bone) or joint infections, pelvic inflammatory disease, strep throat, pneumonia, acute otitis media, and endocarditis. It can also be used to treat acne, and some cases of methicillin-resistant Staphylococcus aureus (MRSA). In combination with quinine, it can be used to treat malaria. It is available by mouth, by injection into a vein, and as a cream or a gel to be applied to the skin or in the vagina.
Azithromycin, sold under the brand names Zithromax and Azasite, is an antibiotic medication used for the treatment of a number of bacterial infections. This includes middle ear infections, strep throat, pneumonia, traveler's diarrhea, and certain other intestinal infections. Along with other medications, it may also be used for malaria. It can be taken by mouth or intravenously.
Rosacea is a long-term skin condition that typically affects the face. It results in redness, pimples, swelling, and small and superficial dilated blood vessels. Often, the nose, cheeks, forehead, and chin are most involved. A red, enlarged nose may occur in severe disease, a condition known as rhinophyma.
Demeclocycline is a tetracycline antibiotic which was derived from a mutant strain of Streptomyces aureofaciens.
Tetracyclines are a group of broad-spectrum antibiotic compounds that have a common basic structure and are either isolated directly from several species of Streptomyces bacteria or produced semi-synthetically from those isolated compounds. Tetracycline molecules comprise a linear fused tetracyclic nucleus to which a variety of functional groups are attached. Tetracyclines are named after their four ("tetra-") hydrocarbon rings ("-cycl-") derivation ("-ine"). They are defined as a subclass of polyketides, having an octahydrotetracene-2-carboxamide skeleton and are known as derivatives of polycyclic naphthacene carboxamide. While all tetracyclines have a common structure, they differ from each other by the presence of chloro, methyl, and hydroxyl groups. These modifications do not change their broad antibacterial activity, but do affect pharmacological properties such as half-life and binding to proteins in serum.
Corneal neovascularization (CNV) is the in-growth of new blood vessels from the pericorneal plexus into avascular corneal tissue as a result of oxygen deprivation. Maintaining avascularity of the corneal stroma is an important aspect of healthy corneal physiology as it is required for corneal transparency and optimal vision. A decrease in corneal transparency causes visual acuity deterioration. Corneal tissue is avascular in nature and the presence of vascularization, which can be deep or superficial, is always pathologically related.
A pimple or zit is a kind of comedo that results from excess sebum and dead skin cells getting trapped in the pores of the skin. In its aggravated state, it may evolve into a pustule or papule. Pimples can be treated by acne medications, antibiotics, and anti-inflammatories prescribed by a physician, or various over the counter remedies purchased at a pharmacy.
Tubal factor infertility (TFI) is female infertility caused by diseases, obstructions, damage, scarring, congenital malformations or other factors which impede the descent of a fertilized or unfertilized ovum into the uterus through the fallopian tubes and prevents a normal pregnancy and full term birth. Tubal factors cause 25-30% of infertility cases. Tubal factor is one complication of chlamydia trachomatis infection in women.
Incyclinide is a chemically modified tetracycline antibiotic that was investigated in clinical trials for the treatment of rosacea, various tumours, allergic and inflammatory diseases and a number of other conditions.
Childhood granulomatous periorificial dermatitis (CGPD), is a rare benign granulomatous skin disease of unknown cause. The disorder was first described in 1970 by Gianotti in a case series of five children. CGPD is more common in boys than girls.